Flexible stamp and method for manufacturing the same

Abstract

The present invention relates to a flexible stamp configured for imprinting, in particular nanoimprinting, and a method for manufacturing said flexible stamp, said flexible stamp comprising a substantially flexible substrate having at least one textured region, at least one functional element and at least two conductive tracks connected or connectable to the at least one functional element.

Description

[Technical field]

[0001] The present invention relates to a flexible stamp configured for imprinting, in particular for nanoimprinting. The present invention also relates to a method for manufacturing such a stamp. The present invention further relates to a system for imprinting, in particular for nanoimprinting. [Background technology]

[0002] Flexible stamps are typically used in nanoimprint processes using roll-to-plate, plate-to-roll, or roll-to-roll techniques. Stamps are typically passive processing tools that act as a mold and / or holder for the texture to be transferred to the product. In particular, current technology flexible stamps are not responsive to individual process parameters (e.g., individual pressure or temperature anomalies or randomly occurring air bubbles under the flexible stamp during processing).

[0003] It is an object of the present invention to provide an improved and / or at least an alternative flexible stamp. Summary of the Invention

[0004] The present invention provides a stamp, in particular a flexible stamp configured for imprinting, in particular for nanoimprinting. The stamp of the present invention comprises at least one substantially flexible substrate, said substrate comprising at least one textured region, at least one functional element and preferably at least two conductive tracks connected or connectable to the at least one functional element. The at least one functional element substantially (completely) covers the at least one textured region and / or overlaps the at least one textured region and / or the at least one functional element is arranged outside the textured region.

[0005] The stamp according to the invention benefits from the presence of at least one functional element. Because the at least one functional element covers and / or overlaps at least one textured region and / or is located outside the textured region, the stamp can benefit from the functional element without the functional element affecting the main performance of the stamp. It is undesirable for the functional element to affect the imprint performance of the stamp. Therefore, the uniform properties of the textured region must be preserved. This is achieved by the functional element being located so as to completely cover or overlap the textured region. This can also be achieved by locating the functional element outside the textured region of the stamp. Such mutual configuration of the textured region and the functional element maintains the uniformity of the textured region. If the functional element partially covers or overlaps the textured region of the stamp, irregularities in the texture of the final product may occur. Here, the final product is the product imprinted and / or textured by the flexible stamp.

[0006] The flexible stamp according to the invention is especially adapted for imprint transfer, texturing and / or transfer by roll-to-roll, plate-to-roll and / or roll-to-plate processes. The stamp according to the invention can transfer a material, for example a resin, ink, coating, etc., to a product, thereby providing a layer of material on the product, similar to the working principle of a clerical stamp. In this mode of operation, the textured area of ​​the stamp can be wetted with an ink or coating material and pressed against the surface of the target product, whereby the part of the stamp wetted with the ink or coating material can appear on the target product. This principle is known as relief imprinting (relief printing). The stamp can be contacted with a liquid, molten or viscous material, either on the stamp itself or on the surface of the target product. The liquid, molten or viscous material can then conform to the texture of the stamp and be hardened, for example by heating, cooling or electromagnetic radiation while in contact with the stamp. When the stamp is removed, the hardened material has a negative image of the stamp, with a texture similar to a wax stain melted on a document by a conventional seal mould. This printing principle is known as intaglio imprinting (intaglio printing). The stamp according to the invention may be used to transfer small solid objects, such as micro LEDs, from an initial surface to a target surface. Regardless of whether the stamp is used for imprinting, embossing or transferring, the stamp may have so-called active areas (areas optimized for the function of imprinting, embossing or transferring). Usually, the active areas are substantially equal to the textured areas. Note that the stamp also means a template or imprint template. The substrate according to the invention is also called a carrier or a sheet. The substrate may be, for example, a sheet-like material (such as a plate, panel, board, foil, laminate or textile) or any other material. The flexibility and / or rigidity depends on the material and its thickness. Preferably, the substrate determines the mechanical properties of the flexible stamp. The functional elements are also called functional structures.The at least one conductive track is also referred to as a conductive path.

[0007] The texture of the texture area is in particular a three-dimensional texture. The texture area may be a three-dimensional texture area having recesses and protrusions. The texture area may be either a negative or a positive image of the texture to be imprinted onto the target product. A positive image of the texture is an image in which the protrusions of the stamp are transferred to the protrusions of the target surface and the recesses of the stamp are transferred to the recesses of the target surface. A negative image is an image in which the protrusions of the stamp are transferred to the recesses of the target surface and the recesses of the stamp are transferred to the protrusions of the target surface.

[0008] For example, at least a portion of the textured region may include a repeating pattern. At least a portion of the textured region may also be a randomized texture. The texture of the textured region may include a diffraction grating, a tilted grating, a blazed grating, a microlens array, lenticules, pillars, bars, pyramids, prism lines, and / or combinations thereof. It is also possible that the substrate comprises at least one active area, and in particular that the active area comprises a texture. The active area may be different from the rest of the stamp, in particular from the rest of the substrate.

[0009] The depth of the texture of the textured region may be, for example, in the nanometer to micrometer dimension. For example, it is conceivable that at least a portion of the texture has a depth in the range of 0.1 nm to 100 μm. It is also conceivable that at least a portion of the texture of the textured region has a height from the maximum peak height to the maximum valley depth of 1 mm or less. Preferably, at least a portion of the texture has a height from the maximum peak height to the maximum valley depth of 10 μm or less, more preferably 5 μm or less, and even more preferably 2 μm or less. However, it is also conceivable that at least a portion of the texture of the textured region has a height from the maximum peak height to the maximum valley depth of 100 nm or less, more preferably 50 nm or less, and even more preferably 20 nm or less or 10 nm or less.

[0010] Typically, in the context of the present invention, the surface of at least one textured region is smaller than the entire surface of the substrate. The textured region may, for example, be located centrally on or within the substrate. The side edges (periphery) of the substrate are preferably free of texture.

[0011] The functional elements may be applied (utilized) to monitor, adjust or control process conditions, for example when the same stamp is used during multiple runs. For example, it is conceivable that in practice at least parts of the stamp or the substrate experience temperature differences during successive or repeated use. For example, parts of the stamp may heat up, affecting the performance of the stamp. At least one functional element may then be used to correct and / or counteract the occurring deviations. In a preferred embodiment, the at least one functional element is a conductive element, in particular an electrically conductive element. It is also conceivable that the at least one functional element is a heat transfer element (thermally conductive element) or a heating element. The application of at least one conductive element is beneficial because the conductive properties of the functional element allow to correct and / or counteract any deviations that occur during the use of the stamp. In this way, more reproducible results, for example identical products, or at least products with reduced product variability, are obtained. The use of at least one functional element, such as a conductive element, allows a longer life of the stamp, since the functional element contributes to the protection of the textured areas by maintaining optimal process conditions during the use of the stamp. The stamp, and in particular the functional elements, may be configured to meet certain prerequisites that must be met for a successful imprint process. Monitoring parameters related to the prerequisites is an effective way to collect data and statistics and perform quality control. Non-limiting examples of these include functional elements that monitor the starting and / or local temperature of the stamp and / or functional elements that monitor the distortion of the stamp during the imprint process.

[0012] Preferably, the at least one functional element surrounds the at least one textured region. It is also conceivable that the at least one functional element forms a functional region. The functional region may cover, overlap or surround the textured region. The functional region may for example be a conductive region. In a preferred embodiment, the functional region is larger than the textured region. The functional region may completely cover or completely surround the textured region, in particular to ensure uniformity of the textured region.

[0013] At least one part of the at least one functional element may be made of at least one conductive material, in particular at least one electrically conductive material (electrically conductive material). In this context, an electrically conductive material is, for example, a material that conducts electrical energy without changing its chemical composition and has an electrical resistance of 100 (Ωmm 2 ) / m or less. Advantageously, the at least one conductive material comprises at least one metal, at least one non-metallic inorganic compound, and / or at least one conductive polymer. It is also conceivable that the at least one conductive material is composed of a combination of these materials. Non-limiting examples of possible metals include iron, aluminum, copper, silver, gold, tin, or alloys thereof. It is also conceivable that the at least one (electrically) conductive material comprises a non-metallic inorganic compound or element, such as, for example, graphite, graphene, carbon nanotubes, carbon fibers, and / or niobium oxide. Furthermore, the conductive material may be a conductive polymer, such as, for example, polyacetylene, poly(3,4-ethylenedioxythiophene), polypyrrole, or other conductive polymers known to those skilled in the art. For example, it is conceivable that the at least one functional element comprises a wire and / or a ribbon. The at least one functional element may comprise a mesh of conductive material and / or a wire mesh.

[0014] It is also conceivable that the at least one conductive material comprises at least one doped metal oxide. The at least one doped metal oxide may for example be selected from the group consisting of tin-doped indium oxide (ITO), antimony-doped tin oxide (ATO), aluminum-doped zinc oxide (AZO), indium-doped zinc oxide (IZO) and / or gallium-doped zinc oxide (GZO). These materials have the advantage of being relatively transparent and / or substantially translucent. This is beneficial since they do not significantly affect the radiation passing through the material that may be necessary for the imprint process in which the stamp is applied (imprint transfer process). Preferably, at least a part of the functional element that covers and / or overlaps the textured area is substantially transparent and / or translucent.

[0015] Preferably, at least a part of at least one substrate is substantially transparent (transmissive) and / or semi-transparent (semi-transparent), especially for visible, ultraviolet and / or infrared radiation. Preferably, at least a part of the stamp, especially at least a part of the substrate, is substantially transparent and / or semi-transparent at the location of the textured area (total). This is important so that the radiation passing through the material (especially the textured area) is not affected. Usually, the rear side (back surface) of the substrate (the surface opposite to the surface with the textured area) is substantially transparent, which facilitates the radiation passing through the material. Preferably, when the at least one functional element substantially completely covers the textured area, the optical properties (e.g. transmission and / or reflectance) of the functional element differ from the optical properties of the textured area by at most 5%. At least a part of the substrate preferably has a transmission of 10% or more, preferably 50% or more, more preferably 90% or more. Preferably, at least a part of the substrate has a UV-A transmission (UV-A transmittance) of 60% or more. For example, at least a portion of the substrate may have a UV-A transparency (UV-A transmittance) in the range of 60% to 100%, particularly in the range of 70% to 90%.

[0016] The substrate may comprise at least one polymer. For example, it is conceivable that at least a part of the at least one substrate comprises polyethylene terephthalate, polyethylene naphthalate, polycarbonate, and / or polyimide. Other non-limiting examples of applicable polymers include poly(methyl methacrylate), polyethylene, polypropylene, and / or cycloolefin polymers. Such materials are known to have good flexibility properties. Alternatively or additionally, the at least one substrate may comprise metal and / or glass (e.g., metal sheets and / or glass sheets). In particular, metal and / or glass may be applied as particles dispersed in the polymer for reinforcement purposes. In a possible embodiment, the substrate may be a laminate of foils of the same or different polymer materials. Alternatively, the substrate may be a laminate of plastic foils and glass panels and / or metal sheets.

[0017] The flexible stamp according to the present invention is typically relatively thin. The thickness of the stamp may be, for example, 1000 μm or less, specifically 750 μm or less, and more specifically 500 μm or less. The thickness of at least one substrate is 500 μm or less (less than 500 μm), preferably 400 μm or less (less than 400 μm), more preferably 300 μm or less (less than 300 μm). It is also conceivable that the thickness of at least one substrate is 250 μm or less, preferably 200 μm or less, more preferably 175 μm or less. The thickness of the substrate is preferably substantially uniform. In particular, the thickness of the substrate in the texture region is substantially uniform. Differences in thickness can affect the performance of the stamp. The stamp, especially the substrate, is preferably bendable up to a radius of 50 cm or less, or up to a radius of 20 cm or less. The stamp is preferably configured to be bent without damaging the stamp and / or without permanently deforming the stamp. Controlling the bendability (flexibility) of the substrate can be useful for any internal and / or external electrical contacts. At least one substrate may have a bend radius in the range of, for example, 5 cm or more and 50 cm or less, 10 cm or more and 40 cm or less, and / or 20 cm or more and 30 cm or less. The bend radius r of the substrate is considered to be 0 cm < r < 50 cm.

[0018] Also, the Young's modulus of at least one substrate is considered to be less than 10 GPa, preferably less than 4 GPa, preferably less than 3 GPa, more preferably less than 2 GPa. Also, the Young's modulus of at least one substrate is considered to be less than 80 GPa, preferably less than 40 GPa, preferably less than 10 GPa, more preferably less than 2 GPa. The Young's modulus is considered to be in the range of 0.1 GPa or more and 200 GPa or less, particularly in the range of 40 GPa or more and 80 GPa or less. The Young's modulus is measured, for example, in accordance with ASTM E111 standard. Embodiments as described above achieve sufficient flexibility without affecting the texture region. The flexibility of at least one functional element may be the same as or higher than that of the substrate.

[0019] In a possible embodiment, the at least one functional element comprises at least one electrical component. The at least one functional element may be an electrical component. The at least one electrical component may be, for example, an RFID unit, an RFID element, or an RFID chip. The at least one electrical component may be a pixelated functional electrical component. In an embodiment, the stamp may comprise at least one functional electrical component. The functional electrical component may be a component or device that converts electrical energy into a different form of energy and thereby performs a function, such as heating, emitting light, mechanical action, force field, or a component or device that performs a function of measuring changes in current or voltage, such as acting as a sensor to measure changes in elongation, temperature, pressure of the stamp. The functional electrical component for heating may be, for example, an electrical resistance heater or a Peltier element that may be used for electrical heating and cooling. The electrical resistance heater or the Peltier element may be used to affect the viscosity of the resin under or near the stamp or to thermally harden the resin. The functional electrical component for emitting light may be, for example, a light-emitting diode. In one embodiment, the light emitting diodes provided on the stamp are thin film light emitting diodes or flexible thin film light emitting diodes. Using functional electric components for light emission, the resin under the stamp can be cured or solidified, for example, by cooling, UV irradiation, evaporation of a solvent, or heating. The functional electric components suitable for mechanical movement can be actuators (for example, piezoelectric actuators or dielectric elastomers) that can perform vibrational or translational movements. By using functional electric components suitable for mechanical movement, several functions can be performed. Vibrational movements can be used to expel gas bubbles from the resin under the stamp, similar to how ultrasound is used for degassing. Furthermore, said movements can affect rheological properties, such as the viscosity, of the resin under or near the stamp. Furthermore, actuators such as piezoelectric actuators can be used as grippers, comparable to tweezers, to grab and release small pieces of solid material. The functional electric elements that convert electrical energy into a force field can be, for example, capacitor plates embedded in the stamp.The capacitor plate may function as part of a dielectric material separating the capacitor plate within the stamp from a second capacitor plate, or as an item acting as a second capacitor plate on the outside of the stamp. Applying a voltage between the two capacitor plates creates an electric field between the inside and outside of the stamp, which may be used to electrostatically bind objects, such as pieces of solid material, to the stamp. Another functional electric device that converts electrical energy into a force field may be an inductive device that creates a magnetic field when electricity flows through it. The magnetic field may be used to selectively bind or release items from the stamp.

[0020] The sensor may convert a physical effect such as strain, pressure, temperature, light, etc., into an electrical signal, which may be amplified for detection. The functional electrical components and / or sensors may be located in part or the entire active area of ​​the stamp, for example to heat the entire area or to detect pressure or strain applied to the stamp inside or outside the active area. The stamp according to the invention may comprise one or more sensors. At least one functional element may be a pixelated functional element. In one embodiment, the functional electrical components are pixelated, meaning that instead of one large functional electrical device in the stamp, multiple small functional electrical components are laid (like tiles) in the active area or part of the stamp, which can be selectively switched on and off or actuated to perform a function at a specific location. The pixelated electrical components may be, for example, pixelated heating pads, pixelated gripper arrays, pixelated piezoelectric actuators, pixelated light sources, or any combination thereof. Actuators such as piezoelectric actuators may also be used as ultrasonic heaters to reduce the viscosity of the resin under or near the stamp. The sensors may be pixelated. That is, the stamp may comprise a pixelated pressure sensor (e.g. a load cell array), a pixelated strain sensor, a pixelated temperature sensor or a pixelated light sensor, or any combination thereof. The pixelated sensor allows specific detection of the physical effect on the area under the stamp. At least two pixelated functional electrical components or pixelated sensors according to the invention are provided in the stamp. The two functional electrical components or sensors do not overlap spatially and can be used selectively with respect to the area they occupy. Throughout this specification, the term "pixelated" should not be understood in the sense that the elements of the pixelated device must form a closed area or be located in close proximity to each other.The elements of a pixelated device may be distributed over an area such that the space between different elements is a multiple of the size of the element.

[0021] In an embodiment, the stamp may comprise a combination of pixelated sensors and pixelated functional electrical components. In an embodiment, at least two sensors may be arranged symmetrically, for example on either side of the active area along the imprint direction. In an embodiment, at least two sensors may be arranged in a line on one or both sides of the active area (also referred to as the start or stop side of the stamp) transverse to the imprint direction. In an embodiment, at least two sensors may be arranged in a circle surrounding the active area or active areas.

[0022] The stamp may further comprise an electrical circuit. In one embodiment, the electrical circuit controls (drives) functional electrical components and / or sensors in the stamp, whether pixelated or not. The electrical circuit may control (drive) the functional electrical components based on data provided by the sensors. In one embodiment, the stamp may comprise an RFID unit that may be inductively contacted by a controller external to the stamp. The RFID unit may be used to store information, such as the type of stamp, the number of cycles of use, or the amount of heat, pressure, or strain stress to which the stamp has been exposed. The RFID device may be used to recognize the stamp in an imprinting, embossing, or transfer system in which the stamp is used. The stamp may comprise at least three electrical contacts. In this case, one of the three electrical contacts may be used for a power connection (also called VVC), another electrical contact may be used for a data connection, and the remaining electrical contact may be used as a common return (often called ground or GND). The electrical contacts may be in the form of a serial or parallel bus. The stamp may have characteristics that change depending on the position in the machine, the substrate to be imprinted provided, and / or depending on data read from sensors on the stamp. The stamp may comprise a pixelated heating pad and be heated depending on the position of the stamp in use, the process step, and / or the imprint settings. The stamp may comprise a pixelated piezoelectric element and be activated depending on the position in use, for example to generate shock waves or vibrations in the resin to facilitate the evacuation of unwanted gases in the resin or bubbles in the resin layer or between the resin and the stamp. The stamp may comprise a pixelated gripper array that is activated depending on the position in use. The stamp may comprise a pixelated load cell array and the load cell data may be adjusted depending on the position in use. The stamp may comprise a pixelated light source and the emission of light, for example for curing or detection purposes, may be adjusted depending on the position in use.The stamp may be powered and / or controlled via galvanically insulating contacts. Contact with the power source may be made, for example, at a roller, belt, chuck, or clamp used to mechanically secure the stamp to other parts of the imprinting, texturing, or transfer device. The stamp may be powered and / or controlled via wires attached to galvanically insulating contacts on the stamp. The stamp may be powered and / or controlled via sliding contacts. The stamp may be powered and / or controlled via capacitive coupling, for example in a clamp or on a roller. The stamp may be powered and / or controlled via inductive coupling. Powering and / or control via inductive and / or capacitive coupling is performed via devices also understood herein as "electrical contacts", but these devices are not in direct material contact but only via electric and / or magnetic fields.

[0023] The at least one functional element preferably includes at least one sensor. The at least one sensor may be used to add additional functionality and controllability to the stamp. For example, the at least one sensor may be a temperature sensor, a strain sensor, a pressure sensor, a position sensor, a force sensor, a piezoelectric sensor, a humidity sensor, or an optical sensor. Multiple sensors may be applied, where the multiple sensors may be the same or different sensors. Furthermore, the at least one functional element may be selected from the group consisting of a heating element, a load cell array, a gripper array, a strain sensor, an identification tag, an RFID tag, a temperature sensor, and / or a piezoelectric element. Non-limiting examples of applicable piezoelectric elements include a piezoelectric actuator, a light emitting diode, a capacitor, and / or any combination thereof. For example, the stamp may comprise multiple sensors (e.g., pressure sensors and / or temperature sensors) distributed on the substrate, each sensor being located outside the textured area. The at least one functional element may be a heating element, such as a heating pad. The at least one functional element may include at least one electrical circuit. The stamp may further comprise or be associated with at least one control unit capable of adjusting at least one functional element based on data obtained during use of the stamp.

[0024] In an advantageous embodiment, the at least one functional element is provided on a surface of the substrate. For example, the at least one functional element may be attached to the surface of the substrate. It is also conceivable that the at least one functional element is provided by deposition, sputtering and / or printing. The at least one functional element may be at least partially embedded in the substrate. That is to say, at least a part of the at least one functional element may be embedded in the substrate and another part of the functional element may be present on the (outer) surface of the substrate. Typically, the at least one substrate comprises a front surface and a rear surface. At least a part of the at least one functional element may be provided on the rear surface of the substrate and a textured area may be provided on the front surface of the substrate. In this way, the functional element may be located at a distance from the textured area. It is also conceivable that the at least one functional element is on the same side of the substrate, but in such a way that the functional element does not overlap and / or interfere with the textured area.

[0025] The stamp may comprise a plurality of functional elements. It is conceivable that the stamp comprises at least two functional elements. The plurality of functional elements may be of the same (type) functional elements. It is also conceivable that the stamp comprises a plurality of functional elements, and that there are at least two different types of functional elements. Thus, for example, it is conceivable that at least one functional element comprises a conductive element and at least one functional element comprises a sensor. It is conceivable that at least one functional element completely covers and / or overlaps at least one textured region, and that at least one functional element is arranged outside the textured region. If a plurality of functional elements are applied, it is conceivable that at least two functional elements are actuated separately. It is also conceivable that at least two functional elements are arranged in parallel and / or in series.

[0026] At least a portion of the at least one textured region is preferably transferred onto the substrate by imprinting, for example, the at least one textured region may be transferred into a resin layer on the substrate by imprinting.

[0027] At least one conductive track, preferably each conductive track, is located at a distance from the textured region. In this way, the conductive track does not affect the performance of the textured region and / or physical properties such as transparency, stiffness, conductivity, etc. of the stamp. At least a part of the functional element may be located outside the surface defined by the textured region, whereby a connection between the conductive track and the functional element can be made at a distance from the textured region. The distance between the textured region and the at least one conductive track is preferably 0.1 μm or more or 0.5 μm or more.

[0028] At least one conductive track (preferably each conductive track) is connected or connectable to at least one functional element. In this way, the conductive track may provide a contact (particularly an electrical contact) between the functional element and another component. The at least one conductive track may, for example, serve as an energy supply to the functional element. For example, it is conceivable that at least a part of the at least one conductive track is provided on the surface of the substrate. This may be done, for example, by deposition, sputtering, printing. It is also conceivable that the at least one conductive track (or each conductive track) comprises a wire (particularly a printed wire). It is also conceivable that at least a part of the at least one conductive track is embedded in the substrate. When multiple conductive tracks are applied, it is desirable that the multiple conductive tracks do not interfere with each other. For example, at least one insulating element may be applied in case of overlapping multiple conductive tracks. That is, the interference of the at least one insulating element also allows multiple conductive tracks to cross or overlap each other. The at least one conductive track may serve as a data connection.

[0029] The stamp may further comprise at least two contacts, in particular electrical contacts. Preferably, at least one (electrical) contact, in particular each (electrical) contact, is connected or connectable to at least one conductive track. The contacts (electrical contacts) may for example be contact areas formed on the stamp, in particular on the substrate, or in the stamp, in particular in the substrate. It is conceivable that the stamp comprises at least two electrical contacts which are connected or connectable directly or indirectly to at least one functional element. The electrical contacts may for example be connected to the at least one functional element via a conductive track. The at least one electrical contact may be at least partially galvanically insulating, capacitive and / or inductive. It is also conceivable that the at least one electrical contact is provided on a clamping element. The at least one clamping element (clamp) allows for example a mechanical and / or electrical attachment of the stamp to an imprinting, texturing or transfer device.

[0030] The stamp may further comprise at least one power supply. Such a power supply may be, for example, an internal power supply embedded in the substrate. It is also conceivable that the stamp comprises an external power supply. Non-limiting examples of power supplies include batteries, solar cells, electromagnetic coils for electromagnetic induction power transmission, or combinations thereof. The stamp may comprise a device for electronically counting process cycles.

[0031] The invention also relates to a system for imprinting, in particular for nanoimprinting, configured to hold at least one stamp according to the invention, comprising at least one steering structure for electrically controlling the movement of the stamp. The invention also relates to a system for imprinting and / or texturing, in particular for nanoimprinting, comprising at least one stamp according to the invention and / or at least one steering structure for electrically controlling the movement of the stamp. The system for imprinting and / or texturing is preferably configured to hold at least one stamp according to the invention. The at least one steering structure may be configured to hold and / or electrically control the movement of the stamp. For example, it is conceivable that the at least one steering structure is configured to be in (direct) contact with at least one conductive track of the stamp. The steering structure may comprise at least one printed galvanically insulating, capacitive and / or inductive electrical connection element. The system may also comprise at least one holding element for holding at least one stamp, for example. The system may be configured for wafer-scale, roll-to-roll or roll-to-plate imprinting. The steering structure may comprise at least one steering belt, preferably a plurality of steering belts. For example, a pair of steering belts may be applied, where the pair of steering belts are arranged on opposite sides of the stamp. The steering structure may comprise a clamping element configured to hold and / or electrically drive the stamp. The clamping element may comprise a top cover, a bottom cover and two screw elements configured to clamp the stamp between the top cover and the bottom cover. The clamping element may further comprise electrically conductive contacts configured to be connected to corresponding contacts on the stamp.The clamping elements may be attached to a steering belt (drive belt), if applicable. The system may comprise contact areas for the energy supply to the stamp, which may for example be provided on a slide rail. When referring to a steering belt (drive belt), this may mean a slide rail and vice versa. In one embodiment, the system according to the invention has the function of controlling the current on the stamp. In this particular embodiment, the flexible stamp comprises electrical contacts extending from the flexible stamp, which are connected to corresponding electrical contacts in the system. The electrical contacts in the system are connected to a power supply (power source) which can be controlled by itself or can be controlled in the connection between the power supply (power source) and the electrical contacts of the system, and a means for controlling the power (such as, for example, a potentiometer or a transistor or any arrangement or combination of these) is provided. In one embodiment, the control of the operation (drive) is possible via wires. In one embodiment, the control of the operation (drive) is possible by adapting the way in which the flexible stamp is attached to the system. In this embodiment, the system may comprise a number of electrical contacts which provide power at different voltages and / or current strengths. In one embodiment, the electrical connection between the system and the flexible stamp is realized through sliding contacts (such as, for example, carbon brushes or current collectors). The system may comprise contacts shaped like conductor rails and the flexible stamp may comprise carbon brushes or current collectors similar to those of an electric train, which constitute the electrical connection between the system and the flexible stamp. In one embodiment, the electrical connection between the system and the flexible stamp is made using a capacitive or inductive connection or any combination thereof. In case of an inductive connection, the system comprises an inductor, for example in the form of an electric coil, as a transmitter and the flexible stamp comprises an inductor, for example in the form of an electric coil, as a receiver.

[0032] In the case of capacitive coupling, both the flexible stamp and the system may comprise two capacitor plates, which may be combined to form two capacitors between the system and the flexible stamp, and when a voltage is applied between the two capacitor plates in the system, a current may flow between the two capacitor plates in the flexible stamp via the capacitive coupling.

[0033] The invention also relates to a flexible stamp configured for imprinting, in particular nanoimprinting, comprising at least one substantially flexible substrate, at least one textured region and at least one functional element, preferably further comprising at least two conductive tracks connected or connectable to the at least one functional element, the at least one functional element completely covering and / or overlapping the at least one textured region and / or the at least one functional element being located outside the at least one textured region. This embodiment can be combined with any of the above-mentioned embodiments.

[0034] The invention also relates to a method for manufacturing a stamp, preferably a stamp according to the invention, in particular configured for imprinting and / or texturing, in particular nanoimprinting, comprising the steps of providing at least one substantially flexible substrate and providing on the substrate at least one textured area, at least one functional element and at least two conductive tracks which are connected or connectable to the at least one functional element, such that the at least one functional element completely covers and / or overlaps the at least one textured area and / or the at least one functional element is arranged outside the textured area.

[0035] The method provides for the manufacture of a stamp according to the invention. Any of the embodiments described above for the stamp can be applied to the method. Preferably, at least one textured area is transferred by imprinting onto the substrate, in particular after the substrate has been provided with at least one functional element and / or at least two conductive tracks. In this way, the provision of the at least one functional element and / or the conductive tracks does not affect the (rather fragile) texture of the substrate. Also, the alignment of the texture to be imprinted in relation to the functional elements is ensured. [Brief description of the drawings]

[0036] The invention is further illustrated by the non-limiting exemplary embodiments shown in the following figures.

[0037] [Figure 1] 1 shows a schematic diagram of a stamp according to a first embodiment of the present invention; [Diagram 2] FIG. 2 shows a schematic diagram of a stamp according to a second embodiment of the present invention. [Diagram 3] FIG. 3 shows a schematic diagram of a stamp according to a third embodiment of the present invention. [Figure 4] FIG. 1 shows a schematic diagram of a flexible stamp attached to the system during use. [Diagram 5] 1 shows a part of a system using a stamp according to the present invention. [Figure 6] 1 is a schematic diagram of an imprint process using a stamp according to the present invention;

[0038] In the above figures, like reference numbers correspond to similar or equivalent elements or features. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] FIG. 1 shows a schematic diagram of a stamp 100 according to a first embodiment of the invention. The stamp 100 is a flexible stamp configured for imprinting, in particular for nanoimprinting. The stamp 100 comprises a substantially flexible substrate 101. The substrate 101 has at least one textured region 102. The stamp 100 further comprises a functional element 103 and two conductive tracks 104 connected to the functional element 103. The illustrated stamp 100 further comprises two contacts 105. Each contact 105 is connected to a conductive track 104. In the illustrated embodiment, the functional element 103 completely covers and overlaps the textured region 102. The conductive tracks 104 are arranged at a distance from the textured region 102. The textured region 102 covers only a portion of the substrate 101 and is located approximately in the center of the substrate 101. The substrate 101 is in particular substantially transparent and / or semi-transparent. The functional element 103 forms a substantially uniform functional region. The functional element 103 may, for example, be substantially arranged behind the textured region 102. The functional element 103 may be substantially transparent and / or semi-transparent.

[0040] FIG. 2 shows a schematic diagram of a stamp 200 according to a second embodiment of the invention. The stamp 200 comprises a substantially flexible substrate 201. The substrate 201 has a textured region 202. The stamp 200 further comprises a number of functional elements 203 and two conductive tracks 204 connected to the functional elements 203. The illustrated stamp 200 further comprises two contacts 205. Each contact 205 is connected to a conductive track 204. The stamp 200 also comprises a data track 206 and a data connector 206 for acquiring data during use of the stamp. The data track 206 may be substantially identical to the conductive track. In the illustrated embodiment, the functional element 203 is arranged outside the textured region 202. The functional element 203 is in particular a sensor (e.g. a pressure sensor). The conductive track 204 is arranged at a distance D from the textured region 202.

[0041] Fig. 3 shows a schematic diagram of a stamp 300 according to a third embodiment of the invention. The stamp 300 comprises a substantially flexible substrate 301. The substrate 301 has a textured area 302. The stamp 300 further comprises a number of functional elements 303 and two conductive tracks 304 connected to the functional elements 303. The stamp 300 comprises contacts 305 integrated in the conductive tracks 304. The stamp 300 further comprises insulating elements 307 at the locations where the two conductive tracks 304 cross or overlap. The conductive tracks 304 may serve as an energy supply source for the functional elements 303. At least one of the conductive tracks 304 may be used as a data connection to the functional elements 303.

[0042] FIG. 4 is a schematic diagram showing a state where the flexible stamp 100 shown in FIG. 1 is attached to a system according to the present invention. The system of FIG. 4 includes a steering structure (driving structure), for example a steering belt (driving belt) 410. The steering belt 410 holds the flexible stamp 100 using a clamp 411 as a clamping element and electrically controls its operation. The illustrated clamp 411 includes an upper cover, a lower cover, and two screw elements configured to clamp the stamp 100 between the upper cover and the lower cover. The clamp 411 further includes conductive contacts 412 connected to corresponding contacts 105 on the flexible stamp 100. The clamp 411 is further attached to the steering belt 410 via an attachment element 414. Furthermore, the clamp 411 includes wires for connecting to an energy supply source and wires for connecting to a data supply source that can be connected to a data contact 413.

[0043] Figure 5 shows a schematic diagram of a system equivalent to that shown in Figure 4. In the system shown in Figure 5, a flexible stamp 200 as shown in Figure 2 and / or Figure 3 is applied to an imprint process. Energy supply contacts (contact areas) 205, 206 are connected to energy supply contacts (contact areas) 517, 518 on a slide rail 516 of the system.

[0044] Contact between contact areas 205 , 206 on the stamp 200 and contact areas 517 , 518 on the slide rail 516 is ensured by a spring 515 which presses the contact areas 205 , 206 against the slide rail 516 .

[0045] FIG. 6 shows a schematic diagram of an imprinting process using a flexible stamp 100 according to the present invention. Also shown is a target product 600 to be transferred by imprinting, which is placed on a carrier 660. A coating unit 661 supplies lacquer (resin). The textured area of ​​the flexible stamp 100 is covered with a layer of lacquer (resin) before the textured area contacts the target product 600. The target product 600 is transported on the carrier 660 so as to pass under the flexible stamp 100. Note that the layer of lacquer (resin) may be applied to the stamp 100 instead of the target product 600, or may be applied to both the target product 600 and the stamp 100. The flexible stamp 100 is fixed to a belt 662 using a clamp 611. The belt 662 and the flexible stamp 100 are guided by (for example a pair of) rollers 663. A slide rail 616 is attached near the (for example one) roller 663. The exact position of the slide rail 616 may vary and is determined by the moment of contact with the flexible stamp 100, for example to allow electrical control of an electrical circuit.

[0046] The present invention is not limited to the exemplary embodiments shown and described herein, but is subject to countless variations within the framework of the appended claims, which are obvious to those skilled in the art, in which case it is conceivable to combine completely or partially the various inventive concepts and / or technical measures of the above-described embodiments without departing from the inventive idea as defined in the appended claims.

[0047] The verb "comprise" and its conjugations as used in this patent specification are understood to mean not only "comprise", but also to include the expressions "include", "substantially comprise", "formed by" and conjugations thereof.

Claims

1. A flexible stamp configured for imprinting, comprising: at least one substantially flexible substrate having at least one textured region; At least one functional element; at least two conductive tracks connected or connectable to at least one said functional element, At least one of the functional elements completely covers and / or overlaps at least one of the textured regions, and / or At least one of the functional elements is located outside the textured region. Flexible stamp.

2. At least one of the functional elements is a conductive element. The flexible stamp of claim 1 .

3. At least one of the functional elements forms a functional area that covers and / or surrounds the textured area.

3. The flexible stamp according to claim 1 or 2.

4. At least a portion of at least one of the functional elements is made of a conductive material. The flexible stamp of claim 1 .

5. The at least one conductive material comprises at least one metal, at least one non-metallic inorganic compound, and / or at least one conductive polymer. The flexible stamp according to claim 4.

6. At least one of the conductive materials comprises a doped metal oxide; 6. The flexible stamp according to claim 4 or claim 5.

7. At least a portion of at least one of the substrates is substantially transparent and / or translucent; The flexible stamp of claim 1 .

8. At least a portion of at least one of the substrates comprises polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, poly(methyl methacrylate), polyethylene, polypropylene, and / or cycloolefin polymer; The flexible stamp of claim 1 .

9. The thickness of at least one of the substrates is less than 500 μm. The flexible stamp of claim 1 .

10. At least one of the substrates has a bend radius in the range of 5 cm to 50 cm. The flexible stamp of claim 1 .

11. The Young's modulus of at least one of the substrates is less than 80 GPa; The flexible stamp of claim 1 .

12. At least one of the functional elements is an electrical component. The flexible stamp of claim 1 .

13. At least one of the functional elements includes at least one sensor. The flexible stamp of claim 1 .

14. the at least one functional element is selected from the group consisting of a heating element, a load cell array, a gripper array, a strain sensor, a temperature sensor, an identification tag, an RFID tag, and / or a piezoelectric element; The flexible stamp of claim 1 .

15. At least one of the functional elements includes at least one electrical circuit. The flexible stamp of claim 1 .

16. At least one of the functional elements is provided on a surface of the substrate. The flexible stamp of claim 1 .

17. At least a portion of at least one of the functional elements is embedded within the substrate. The flexible stamp of claim 1 .

18. At least one of the substrates has a front surface and a rear surface; at least one further functional element is provided on the rear side of the substrate; the textured region is on the front surface; The flexible stamp of claim 1 .

19. A plurality of the functional elements are provided. The flexible stamp of claim 1 .

20. At least one of the plurality of functional elements completely covers and / or overlaps at least one of the textured regions, and At least one of the plurality of functional elements is disposed outside the texture region.

20. The flexible stamp of claim 19.

21. at least one of the textured regions is transferred onto the substrate by imprinting; The flexible stamp of claim 1 .

22. at least one of the conductive tracks is at least partially provided on the surface of the substrate; and / or at least one of the conductive tracks is at least partially embedded in the substrate; The flexible stamp of claim 1 .

23. At least one of the conductive tracks is spaced apart from the textured region. The flexible stamp of claim 1 .

24. at least two electrical contacts; each said electrical contact is connected or connectable to at least one said conductive track; The flexible stamp of claim 1 .

25. At least one of the electrical contacts is at least partially galvanically insulating, capacitive, and / or inductive.

25. The flexible stamp of claim 24.

26. At least one of the electrical contacts is provided on a clamping element.

26. The flexible stamp according to claim 24 or claim 25.

27. at least one power supply; The flexible stamp of claim 1 .

28. A method of manufacturing a stamp configured for imprinting, comprising: providing at least one substantially flexible substrate; providing on the substrate at least one textured region, at least one functional element and at least two conductive tracks connected or connectable to at least one functional element, such that at least one functional element completely covers and / or overlaps at least one textured region and / or is located outside the textured region, method.

29. the textured region is transferred onto the substrate by imprinting; 29. The method of claim 28.

30. A system for imprinting, comprising: A flexible stamp holder configured to hold at least one flexible stamp according to claim 1, at least one steering structure for electrically controlling the movement of the flexible stamp; system.

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