JP2013517625A - Nanopattern forming method and apparatus - Google Patents

Abstract

Embodiments of the present invention relate to methods and apparatus that are useful in nanopatterning large area substrates, wherein mobile nanostructured films are used to image radiation sensitive materials. Nanopatterning technology utilizes near-field photolithography, and the nanostructured film is used to adjust the light intensity reaching the radiation sensitive layer. Near-field photolithography may utilize an elastomeric phase shift mask or may use surface plasmon technology, where the movable film includes metal nanoholes or metal nanoparticles.
[Selection figure] None

Description

  Embodiments of the present invention relate to nanopatterning methods that can be used to pattern a substrate, such as a large substrate or a film that may be sold as a rolled article. Other embodiments of the invention relate to an apparatus that may be used to pattern a substrate and that may be used to implement method embodiments, including methods of the type described.

  This section describes background subject matter related to the disclosed embodiments of the present invention. There is no intention to express, either explicitly or implicitly, that the background art discussed in this section legally constitutes prior art.

  Nanostructure formation is necessary for many applications and industries and for new technologies under development. Efficiency improvements can be achieved for current applications in areas such as solar cells and LEDs, and for example, but not by way of limitation, next generation data storage devices.

  Nanostructured substrates can be produced using techniques such as direct electron beam lithography, deep ultraviolet lithography, nanoparticle lithography, nanoimprint lithography, near-filled phase shift lithography, and plasmonic lithography. May be used.

  Nanoimprint lithography (NIL) creates a pattern by mechanical deformation of an imprint resist followed by subsequent processing. Imprint resists are typically monomeric or polymeric formulations that are cured by heat or UV light during imprinting. There are many variations of NIL. However, two of these processes appear to be the most important. These are thermoplastic nanoimprint lithography (TNIL) and step-and-flash nanoimprint lithography (SFIL).

  TNIL is the earliest and most mature nanoimprint lithography. In the standard TNIL process, a thin layer of imprint resist (thermoplastic polymer) is spin coated onto a sample substrate. A mold having a predetermined topological pattern is then brought into contact with the sample and pressed against the sample under a given pressure. When heated above the glass transition temperature of the thermoplastic polymer, the pattern on the mold is pressed into the melt of the thermoplastic polymer film. After the sample with the pressed mold is cooled, the mold is separated from the sample, leaving the imprint resist on the sample substrate surface. This pattern does not penetrate the imprint resist. There is a residual thickness of unmodified thermoplastic polymer film remaining on the sample substrate surface. A pattern transfer process such as reactive ion etching can be used to transfer the pattern in the resist to the underlying substrate. The variation in the residual thickness of the unchanged thermoplastic polymer film presents problems with the uniformity and optimization of the etching process used to transfer the pattern to the substrate.

  VTT's Tapio Makela et al., A Finnish technology research center, published information about a custom-made, laboratory-scale roll-to-roll imprinting tool dedicated to producing high-throughput, submicron structures. Hitachi et al. Developed a sheet or roll-to-roll basic NIL machine and demonstrated its ability to process a 15 meter long sheet. The goal is to create a continuous imprint process using a belt molding (nickel-plated mold) to imprint polystyrene sheets for large geometric applications such as fuel cells, batteries and possibly display membranes. Was to do.

  Hua Tan et al. At Princeton University publishes two implementations of roller nanoimprint lithography. That is, rolling a cylindrical mold on a flat, hard substrate and pressing a flat mold directly onto the substrate to roll a smooth roller over the mold. Both methods are based on the TNIL approach, where the roller temperature is set above the glass transition temperature, ie the Tg of the resist (PMMA), while the platform is set at a temperature below the Tg. Currently, the prototype tool does not provide the desired throughput. Furthermore, there is a need to improve reliability and reproducibility for imprinted surfaces.

  In the SFIL process, a UV curable liquid resist is applied to a sample substrate and the mold is made of a transparent substrate such as fused silica. After the mold and sample substrate are pressed together, the resist is cured using UV light and becomes a solid. After separation of the mold from the cured resist material, a pattern similar to that used in TNIL may be used to transfer the pattern to the underlying sample substrate. Dae-Geun Choi of the Korea Mechanical Research Institute has proposed using a fluorinated organic-inorganic hybrid mold as a stamp for nanoimprint lithography, which releases it from the substrate material No anti-stiction layer is required.

  Since nanoimprint lithography is based on mechanical deformation of the resist, there are a number of challenges in both SFIL and TNIL processes in static step-and-repeat or roll-to-roll implementations. These challenges include template life, throughput rates, imprint layer tolerances, and critical dimension control during transfer of the pattern to the underlying substrate. The remaining non-imprinted layer that remains after the imprinting process requires an additional etching step prior to the main pattern transfer etch. Defects can be created by inadequate filling and shrinking of the negative pattern, which often occurs with polymeric materials. The difference in coefficient of thermal expansion between the mold and the substrate creates lateral distortions that are concentrated at the corners of the pattern. This distortion induces defects and causes fracture defects at the base of this pattern during the mold release process.

  Soft lithography is an alternative to photolithography as a microfabrication and nanofabrication method. This technique relates to replica molding of self-assembled monolayers. In soft lithography, an elastomeric stamp having a relief structure patterned on the surface is used to produce patterns and structures having processing dimensions in the range of 30-100 nm. The most promising soft lithography technique is microcontact printing (μCP) using a self-assembled monolayer (SAMS). The basic process of μCP includes: 1. A polydimethylsiloxane (PDMS) mold is dipped into a solution of a specific substance. This particular material can form a self-assembled monolayer (SAM). Such a specific substance may be called ink. This particular material adheres to the protruding pattern on the master surface of this PDMS. 2. The PDMS mold is contacted with the surface of the metal-coated substrate, such as gold or silver, with the surface coated with this material facing down, so that only the pattern on the surface of the PDMS mold is this Contact with a metal coated substrate. 3. This specific material forms a chemical bond with the metal so that only the specific material on the protruding pattern surface still remains on the metal coated surface after removing the PDMS mold. This particular material forms a SAM that extends approximately 1-2 nanometers above the metal-coated surface (just like an ink on a piece of paper) on a metal-coated substrate. 4). The PDMS mold is removed from the metal-coated surface of the substrate, leaving a patterned SAM on the metal-coated surface.

  Optical lithography does not use mechanical deformation or phase change of resist material like nanoimprint lithography, and does not have material management problems like soft lithography, so better processing part replication accuracy and further manufacturability Provides high processing. While regular optical lithography has limited resolution due to diffraction, several new optical lithography techniques based on the near-field evanescent effect already have advantages in printing sub-100 nm structures, albeit only on a small area. Demonstrated. Near-field phase shift lithography NFPSL exposes a photoresist layer to ultraviolet (UV) light passing through the mask while the elastomeric phase mask is in conformal contact with the photoresist. Is involved. Contacting an elastomeric phase mask with a thin layer of photoresist causes the photoresist to “wet” the surface of the contact surface of the mask. When UV light is passed through the mask while the mask is in contact with the photoresist, the photoresist is exposed to a light intensity distribution that makes up the surface of the mask. In the case of a mask having a relief depth designed to adjust the phase of the transmitted light by π, an intensity local zero appears at the edge of the relief step. If a positive photoresist is used, exposure through such a mask followed by development yields a photoresist line having a width equal to the characteristic width of zero intensity. For 365 nm (near ultraviolet) light combined with a conventional photoresist, the width of zero intensity is approximately 100 nm. The PDMS mask can be used to form a conformal, atomic scale contact with a flat, solid layer of photoresist. This contact is established spontaneously upon contact without any applied pressure. The overall adhesion forces guide this process and provide a simple and convenient way to align the mask at an angle and position that is normal to the photoresist surface to establish full contact. . There is no physical gap for this photoresist. PDMS is transparent to UV light having a wavelength greater than 300 nm. When light passes through the PDMS from a mercury lamp (the main spectral line is 355-365 nm) while the PDMS is in conformal contact with the layer of photoresist, the photoresist is created in the mask. Exposed to the intensity distribution.

  In 2006, the 32nd International Conference on Micro and Nano Engineering, “Near-Field Lithography as a non-fabrication tool as a near-field nanolithography tool. A step-and-repeat near-field nanolithography developed by (Canon, Inc.) has been described. Near field lithography (NFL) is used where the distance between the mask and the photoresist to which the pattern is to be transferred is as close as possible. The initial distance between the mask and the wafer substrate was set to about 50 μm. This patterning technique has been described as a “three-layer resist process” using very thin photoresist. A pattern transfer mask was attached to the bottom of the pressure vessel and pressurized to achieve "perfect physical contact" between the mask and the wafer surface. This mask was “deformed to fit the wafer”. The initial 50 μm distance between the mask and the wafer is said to allow the mask to move to another position for exposure and patterning of areas greater than 5 mm × 5 mm. This patterning system utilized i-line (365 nm) radiation from a mercury lamp as a light source. Successful patterning of a 4 inch silicon wafer having a structure smaller than 50 nm has been accomplished by such a step-and-repeat method.

  In Non-Patent Document 1, Kunz et al. Applied near-field phase shift mask lithography to nanopatterning of flexible sheets (polyimide films) using a rigid fused silica mask and deep UV wavelength exposure. In Non-Patent Document 2, Maria et al. Presented experimental and computational studies of phase shift photolithography technology using a two-component elastomer mask in conformal contact with a layer of photoresist. This study was optimized by casting the prepolymer in contact with the anisotropically etched structure of single crystal silicon on SiO2 / Si and curing it to elastomeric poly (dimethylsiloxane). Incorporate a mask. The authors report that the PDMS phase mask can be used to form resist features in the overall relief geometry on the mask.

  Title of the invention “Transparent Elastomeric, Contact-Mode Photographic Mask, Sensor, and Wavefront Engineering Element, Wave Forming Elements and Elements” issued on June 22, 2004. U.S. Patent No. 5,637,097 to Rogers et al. Describes a contact mode photolithographic phase mask comprising a diffractive surface having a plurality of indentations and protrusions. The protrusion is brought into contact with the surface of the positive photoresist, and the surface is exposed to electromagnetic radiation through a phase shift mask. The phase shift due to radiation passing through the indentation facing the protrusion is substantially complete. Thereby, a minimum value of the intensity of the electromagnetic radiation is generated at the boundary between the indentation and the protrusion. The elastomer mask matches well with the surface of the photoresist, and after development of the photoresist, processed features smaller than 100 nm can be obtained (summary). In one embodiment, a reflective plate is used outside the substrate and contact mask so that the radiation will be bounced back to the desired location with a shifted phase. In another embodiment, the substrate may be shaped in a manner that causes deformation of the phase shift mask and affects the behavior of the phase shift mask during exposure.

  Near-field surface plasmon lithography (NFSPL) utilizes near-field excitation to induce photochemical or photophysical changes to produce nanostructures. The main near-field technology is based on local field enhancement around metal nanostructures when irradiated at the surface plasmon resonance frequency. Plasmon printing consists of the use of plasmon-guided evanescent waves through the metal nanostructure to create photochemical or photophysical changes in the underlying layer of the metal nanostructure. In particular, a silver nanometer in close proximity to a thin film of g-ray photoresist (AZ-1813 available from Micro Chemicals GmbH, Ulm, Germany, AZ-Electronic Materials). Exposure of the particles to visible light (λ = 410 nm) can produce selectively exposed areas having a diameter smaller than λ / 20. W. Srituravanich et al. In Non-Patent Document 3 to excite SP on a metal substrate to enhance transmission through a periodic sub-wavelength opening using a wavelength that is effectively shorter than the excitation light wavelength. The use of near ultraviolet light (λ = 230 nm to 350 nm) is described. A plasmon mask designed for lithography in the UV range consists of an aluminum layer drilled with a two-dimensional periodic array of holes and two surrounding dielectric layers (one on each side). Aluminum is chosen because it can excite SP in the UV range. Quartz is used as the mask support substrate, along with a poly (methyl methacrylate) spacer layer that acts as an adhesive to the aluminum foil and as a dielectric between aluminum and quartz. Poly (methyl methacrylate) is used in combination with quartz. This is because at the exposure wavelength (i-line at 365 nm) they are transparent to UV light and have equivalent dielectric constants (quartz and PMMA, 2.18 and 2.30, respectively). A sub-100 nm dot array pattern with a period of 170 nm was successfully generated using 365 nm wavelength exposure radiation. Apparently, the total patterning area was about 5 μm × 5 μm, but the issue of scalability is not discussed in the above paper.

  Joseph Martin has proposed a proximity masking device for near-field lithography in US Pat. No. 6,057,017, where a cylindrical block covered with a metal film is connected to one end of the cylinder (the cylinder's end) for internal reflection of light. Used to guide light against the bottom), which includes a pattern of surface relief used for near-field exposure. This block is kept some close distance (“very little but not zero”) from the photoresist on the sample. The cylinder is oriented horizontally using some precision machinery used to pattern the photoresist areas.

  The idea disclosed about using a roller for optical lithography can only be found in US Pat. No. 6,037,028, published on Nov. 13, 1984, entitled “Large Area Exposure Apparatus”. Toshio Aoki et al. Describe the use of a transparent cylindrical drum that can rotate and advance with an internal light source and a film of patterned photomask material attached to the outside of the cylindrical drum. . A film of transparent heat reflective material is present inside the drum. A substrate having an aluminum film on the surface and a photoresist overlying the aluminum film is contacted with a patterned photomask on the drum surface, and imaging light passes through the photomask and passes through the aluminum film. The photoresist on the surface of the film is imaged. This photoresist is then developed to give a patterned photoresist. This patterned photoresist is then used as an etching mask for the aluminum film present on the substrate.

There is no mention of the type of material used as a photomask film or as a photoresist on the surface of the aluminum film. A high pressure mercury lamp light source (500 W) was used to image the photoresist overlying the aluminum film. A glass substrate of about 210 mm (8.3 inches) by 150 mm (5.9 inches) and a thickness of about 0.2 mm (0.008 inches) was produced using a cylindrical drum pattern transfer apparatus. The feature size of the pattern transferred using this technique was a square with dimensions of about 22.2 μm × 22.2 μm, apparently about 500 μm ² . This processing dimension was based on the approximate pixel size of the LCD display at the time the patent application was filed in 1984. It was said that the photomask film outside the cylindrical drum can hold about 140,000 pattern transfer. The contact lithography scheme used by Toshio Aoki et al. Cannot produce sub-micron features.

  Soft lithography using nanoimprinting methods (thermal curing or UV curing) or printing using SAM materials does not appear to be a highly manufacturable process. In general, imprinting methods produce deformation of the substrate material due to heat treatment (eg, thermal NIL), or shrinkage of patterned features (UV cured polymer features) where the polymer cures. Due to the application of pressure (hard contact) between the stamp and the substrate, virtually no defects can be avoided and the stamp has a very limited lifetime. Soft lithography has certain advantages in that it is a heat and load free (stressless) printing technique. However, the use of SAM as an “ink” for sub-100 nm patterns is very problematic due to molecular drifting on the surface, and application to large areas has also been confirmed experimentally It has not been.

  Early researchers have proposed a method for nanopatterning large area rigid and flexible substrate materials based on near-field photolithography described in US Pat. Here, a rotatable cylindrical or conical mask is used for imaging the radiation sensitive material. This nanopatterning technique uses near-field photolithography, and a mask used to pattern the substrate contacts the substrate. Near-field photolithography may utilize an elastomeric phase shift mask, or may utilize surface plasmon technology, where the rotating cylinder surface contains metal nanoholes or nanoparticles.

US Pat. No. 6,753,131 US Pat. No. 5,928,815 JP 592004419A International Publication No. 20099094009 US Patent Application No. 2009029789

“Large-area patterning of 50 nm structures on flexible substituting using near-field 193 nm radiation” (large area patterning of 50 nm structures on flexible substrates using near-field 193 nm radiation), JVST B 21 page 78 "Experimental and computational studies of phase shift lithography with binary elastomeric masks (experimental and computational studies of phase shift lithography using two-component elastomer masks)", JVST B 24, page 5 (page 28). “Plasmonic Nanolithography”, Nanoletters V4, N6 (2004), pp. 1085-1088

  Embodiments of the present invention relate to methods and apparatus that are useful in nanopatterning large area substrates, rigid, flat or curved objects, or flexible films. Nanopatterning technology utilizes near-field UV photolithography, where the mask used to pattern the substrate is in contact with the substrate. Near-field photolithography may include a phase shift mask or surface plasmon technology. The near-field mask is manufactured from a flexible film, which is not nanostructured according to the desired pattern. In the method of phase shift, an elastomer film that is not nanostructured, such as a film of polydimethylsiloxane (PDMS), can be used. Nanostructuring can be done using laser processing, selective etching, or other available techniques, or known nanofabrication methods (electron beam writing, holographic lithography, laser direct writing, or nanoimprinting steps). This can be done by replication (molding, casting) from a nanostructured “master” made using and repeat or roll-to-roll lithography. This film can be supported by another transparent flexible film (carrier). In the plasmon method, a film using a metal layer having a nanohole structure made using one of the methods described above or, for example, by depositing metal nanoparticles deposited from a colloidal solution can be used. . In order to provide a uniform contact area for near field lithography, we rely on van der Waals forces of static friction between the elastomeric film and the photoresist layer on the substrate. Alternatively, a transparent cylinder is used to provide controllable contact between the nanostructured film and the substrate. Such cylinders may have flexible walls and can be pressurized with a gas to provide a controllable pressure between the nanostructured film and the substrate. .

  The manner in which exemplary embodiments of the invention are accomplished will refer to the specific description provided above and to the detailed description of the exemplary embodiment for which applicant has provided drawings. It is clear and understandable in detail. The drawings are provided only as necessary to understand the exemplary embodiments of the present invention, and certain well-known processes and devices are described herein so as not to obscure the inventive nature of the main subject matter of the present disclosure. It should be understood that it is not illustrated in the document.

FIG. 1A shows a cross-sectional view of an embodiment of a flexible nanostructured film 1 having phase shift mask properties. The surface relief nanostructure 3 is made on one of the surfaces of the film 2. FIG. 1B shows a cross-sectional view of an embodiment of a flexible nanostructured film 1 having plasmon mask properties. An array of nanoholes is made in the film or an array of nanoparticles is deposited on the surface. FIG. 2 shows the proposed nanopatterning system before processing begins. The nanostructured film 1 is wound around support drums 4 and 5. The substrate 6 has a photoresist layer 7 deposited on its surface. FIG. 3 shows another embodiment, where the nanostructured film 1 can be wound from one roll 4 to another. FIG. 4 shows the starting point of processing when the film 1 comes into contact with the photoresist 7 using the movable arm 8. FIG. 5 shows the patterning process when the arm 8 is removed from the film-substrate contact, the substrate 6 moves in one direction, and the UV light source 7 illuminates the contact area between the film and the substrate. FIG. 6 illustrates another embodiment, where the nanopatterned film is in contact with the substrate at a significantly larger surface area. FIG. 7 shows an embodiment, in which a transparent cylinder 11 is used to contact the nanostructured film 1 with the photoresist 7 on the substrate 6. FIG. 8 shows an embodiment where the substrate is a flexible film 12 that can be moved from one roll 14 to another. FIG. 9 shows an embodiment where the substrate is nanopatterned from both sides.

  As a prelude to the detailed description, it should be noted that, as used in the specification and claims, the singular forms “a”, “an”, and “the” If there is clearly no indication of different intentions, a plurality of indication objects are included.

  Where the term “about” is used in this application, this is positioned to mean that the nominal value presented is within ± 10% accuracy.

  Embodiments of the present invention relate to methods and apparatus that are useful in nanopatterning large area substrates, wherein a flexible nanostructured film is used to image a radiation sensitive material. Nanopatterning technology utilizes near-field photolithography, the wavelength of radiation used to image the radiation-sensitive layer on the substrate is 650 nm or less, and the mask used to pattern the substrate is in contact with the substrate . Near-field photolithography may utilize a phase shift mask, or may use surface plasmon technology, and the metal layer on the surface of the movable flexible film may contain nanoholes or metal nano Particles are dispersed on the surface of such a flexible film. The detailed description provided below is a sampling of the possibilities that would be recognized by one skilled in the art after reading the disclosure of this application.

  One of those embodiments proposes a phase shift mask approach and is implemented with a flexible nanostructured film. The problem of providing uniform and permanent contact between such a flexible nanostructured film and the substrate is that a strong but temporary bond can be made to the photoresist layer. It is eliminated by manufacturing this film from the material. An example of such a material is an elastomer, such as polydimethylsiloxane (PDMS). PDMS films can be used to form conformal, atomic scale contacts with flat, solid photoresist layers. This contact is established spontaneously upon contact without any applied pressure. An illustration of such a film is shown in FIG. 1A, where film 2 has nanostructures 3 in the form of a transparent surface relief.

  Film 2 may be made from one material (eg, PDMS), or may be made from a composite or multiple layers of two or more materials, for example, nanostructured PDMS It can be laminated or deposited on transparent and flexible support films. Such support films can be made from polycarbonate (PC), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), amorphous fluoropolymer, such as CYTOP, and other materials. The deposition of PDMS on a transparent flexible support film can be done using one of the available techniques such as dipping, spraying, or casting. The support film can be treated with an adhesion promoter to promote better adhesion between the elastomeric film and the polymeric film support, such as oxygen plasma, UV ozone, corona discharge, or silane.

  Another embodiment of a “sticky” material that can be used in place of an elastomer to create dynamic contact with the photoresist is a crosslinked silane material. Such materials can be deposited from silane precursors (self-assembled monolayers, commonly used to deposit SAMs) using large amounts of water / humidity. For example, DDMS (dichlorodimethylsilane) creates a very sticky surface when deposited with a large amount of moisture. In this embodiment, the carrier layer is nanostructured using one of the known nanostructuring techniques (preferably roll-to-roll nanoimprinting lithography) and then coated with a silane material to “stick”. provide.

  A surface relief for phase shift lithography may be made in an elastomer or silane film using any of the following methods: First, a “nanostructured“ master ”is available for nanofabrication technology (depth One of UV stepper, electron beam, ion beam, holography, laser treatment, embossing, nanoimprinting, and others). Second, replicas of the desired nanostructures can be obtained from such masters on the surface of an elastomeric film using casting or molding, for example, in roll-to-roll mode or step-and-repeat mode. .

  In another embodiment, the carrier layer is nanostructured using one of the known nanostructuring techniques (preferably roll-to-roll nanoimprinting lithography) and then coated with an elastomeric material (such as PDMS) Or coated with a silane material (such as DDMS) to provide “stickiness”.

  The nanostructure of such a mask can be designed to function as a phase adjuster, in which case the height of the feature should be proportional to π. For example, for an exposed wavelength of 365 nm, a PDMS material having a refractive index of 1.43 should have a workpiece with a depth of about 400 nm to produce a phase shift effect. In this case, a local minimum in intensity occurs at the step edge of the mask. For example, 20 nm to 150 nm lines can be obtained in the photoresist corresponding to the position of the surface relief edge in the phase shift mask. Thus, this lithography has image reduction properties and nanostructures can be achieved on the mask using larger features.

  Another embodiment uses nanostructures on a flexible mask that functions as a 1: 1 replication mask. As proven in previous publications, for example, Tae-Woo Lee et al., In Advanced Functional Materials, 2005, 15, 1435, depending on the specific parameters of photoresist exposure and development, can be used for photo-masking. Using 1: 1 replication of the feature to resist or phase shift on the surface relief edge on the same elastomeric mask, shrinkage of the feature size can be achieved. In particular, underexposure or underdevelopment over the normal exposure and development time results in a significant difference between the effective exposure in the non-contact and contact areas of the mask. This can be used to generate a 1: 1 replication from mask to photoresist in positive or negative tones (depending on the type of photoresist).

  Another embodiment proposes a plasmon mask approach. Such a plasmon film may be the flexible metal film shown in FIG. 1B having an array of nanoholes according to the desired pattern. Alternatively, the metal layer is deposited on a flexible transparent film. Metal layer patterning uses one of the available nanopatterning techniques (deep UV stepper, electron beam, ion beam, holography, laser processing, embossing, nanoimprinting, and others), followed by Can be done using metal layer etching.

  Alternatively, nanopatterning can be produced using the method described above on a transparent film, and then a metal material can be deposited on the nanopatterned resist, followed by lift-off of the metal layer. .

  Yet another embodiment uses metal nanoparticles distributed in a controllable manner on the surface of a flexible transparent film to produce a plasmon mask. For example, the metal nanoparticles can be mixed with the PDMS material in the liquid phase prior to depositing the PDMS material on a flexible transparent support film. Alternatively, the metal nanoparticles can be deposited on a nanotemplate made in an elastomer layer.

  The nanostructured film can be wound around support drums 4 and 5 and can be kept under controllable tension, as shown in FIG.

  Alternatively, the nanostructured film can be wound from one roll 4 to another roll 5 as shown in FIG.

  The process begins by contacting the nanostructured film 1 with a photoresist 7 deposited on a substrate 6, using a movable arm 8, as shown in FIG. Such contact utilizes Van der Waals forces and temporarily attaches the film to the photoresist. Then, as shown in FIG. 5, the movable arm 8 is removed from the film-substrate contact and the light source, which may include a light focus, collimating, or filtering system 9, is turned on and into the film-substrate contact area. The substrate 6 is moved in one direction using a constant or variable speed. Such movement also moves the film in its direction of movement, exposing different portions of the substrate for the same or different patterns, depending on the nanostructures made on the film.

  Another embodiment, presented in FIG. 6, shows a nanostructured film that contacts the photoresist over a larger area. The contact area starts moving as soon as the base starts moving in a certain direction. The width of the contact area between the nanostructured film and the substrate can be varied by changing the relative position between the substrate 6 and the drums 4 and 5, and the adhesion of the nanostructured film material. It can be changed by changing gender. This configuration can also increase the area of exposure of the nanostructured film to light, thereby improving the throughput of the method due to increased dynamic exposure. help.

  If the nanostructured film surface contact is not sufficiently sticky (eg, as in the case of a plasmon mask approach), the movable arm does not retract and the nanostructured film and substrate are not retracted. Keep controllable and uniform pressure between. For example, the movable arm can be manufactured in the form of a transparent cylinder 1 as shown in FIG. The cylinder is operated by a mechanical system that provides controllable and uniform contact between the nanostructured film and the substrate. In this case, the light source of the illumination 9 can be arranged inside such a cylinder.

  Such a cylinder can be made from a transparent flexible material and can be pressurized with a gas. In such a case, the contact area and pressure between the mask and the substrate can be controlled by the pressure of the gas.

  The gas can flow constantly through the flexible-walled cylinder, creating the necessary controllable pressure and simultaneously cooling the light source located in this cylinder.

  The disclosed nanopatterning method can be used to pattern a flexible film 12, as shown in FIG. 8, from one roll 14 to another roll 13 during exposure. It is movable.

  The disclosed nanopatterning method can be used to pattern rigid or flexible materials from both sides, as shown in FIG.

  The disclosed nanopatterning method can be used to pattern a non-planar or curved substrate, as shown in FIG. FIG. 10a shows how the cylinder on the movable arm follows the curvature of the substrate, and FIG. 10b shows how the flexible-wall gas pressurized cylinder follows the curvature of the substrate. In the latter case, instead of moving the arm in the vertical direction, the pressure in the cylinder can be adjusted to accommodate the deviation in substrate height caused by the curvature.

Claims (31)

A nanopattern forming method comprising:
(A) providing a substrate, the substrate having a radiation sensitive layer on its surface;
(B) providing a movable nanostructured film;
(C) contacting the nanostructured film with the radiation-sensitive layer on the substrate along a contact surface;
(D) dispersing the radiation through the contact while moving the substrate relative to the film;
Including a method.   The method of claim 1, wherein the nanostructured film produces a light intensity adjustment in the plane of the radiation sensitive layer.   The method of claim 2, wherein the nanostructured film has a surface relief.   The method of claim 3, wherein the nanostructured film is a phase shift mask that produces radiation to form an interference pattern in the radiation sensitive layer.   The method of claim 2, wherein the nanostructured film is made of a conformal elastomeric material.   The method of claim 2, wherein the nanostructured film is made of two or more layers of transparent flexible material.   The method of claim 6, wherein the outer layer is made of an elastomeric material.   The method of claim 6, wherein the outer layer is made of a silane material.   4. The method of claim 3, wherein the surface relief is made from a nanostructured master substrate by molding or casting.   The method of claim 2, wherein the conformal nanostructured film is a plasmon mask.   The method of claim 10, wherein the plasmon mask is made of a metal film having an array of nanoholes.   11. The method of claim 10, wherein the plasmon mask is made using a nanopatterned metal layer deposited or laminated on a transparent flexible film.   The method of claim 10, wherein the plasmon mask is formed by an array of metal nanoparticles deposited on a transparent flexible film.   The method of claim 1, wherein the contact between the nanostructured film and the radiation sensitive layer is made using a movable arm.   The method of claim 14, wherein the movable arm is removed from the contact during exposure of the photosensitive layer.   15. The method of claim 14, wherein the movable arm is a cylinder, and the cylinder is rotated and simultaneously contacts the nanostructured film.   The method of claim 16, wherein the cylinder has a flexible wall and is pressurized with a gas.   The method of claim 16, wherein a light source is disposed within the cylinder.   The substrate moves in a direction toward the contact line of the nanostructured film or away from the contact line of the nanostructured film during dispersion of radiation from the contact line. Item 2. The method according to Item 1.   The method of claim 1, wherein the nanostructured film is moved in a closed loop.   The method of claim 1, wherein the nanostructured film is transferred from roll to roll.   The method of claim 1, wherein the substrate is a rigid plate.   The method of claim 1, wherein the substrate has a curvature.   The method of claim 1, wherein the substrate is a flexible film.   Further nanostructured flexible films and light sources are provided on both sides of the substrate, on the other side of the substrate coated with a photosensitive layer, for nanopatterning on both sides of the substrate. The method according to claim 1. An apparatus for performing nanopattern formation,
(A) a nanostructured film;
(B) providing radiation at a wavelength of 650 nm or less through a portion of the nanostructured film, wherein the portion comprises a radiation source in contact with a layer of radiation sensitive material. ,apparatus.   27. The device of claim 26, wherein the nanostructured film is a polymer having a surface relief.   27. The device of claim 26, wherein the nanostructured film is a perforated metal film or a polymer film having metal nanoparticles.   27. The apparatus of claim 26, wherein the nanostructured film has two or more layers.   27. The apparatus of claim 26, wherein a movable cylinder is provided to control a nanostructured film in contact with the radiation sensitive layer.   32. The apparatus of claim 30, wherein the cylinder is pressurized with a gas.

Images