Method for generating three-dimensional structure and laser lithographic apparatus

Abstract

The invention relates to a method for generating a three-dimensional structure in a lithographic material (12), comprising the following steps: receiving the lithographic material (12) by means of a lithographic material receptacle (14); generating an input laser beam (20) by means of a laser beam source (18); demultiplexing the input laser beam (20) by temporally splitting the input laser beam (20) to form a plurality of laser write beams (26); focusing the plurality of laser write beams (26) by means of an objective lens (70); a three-dimensional structure is generated in a lithographic material (12) by means of a focused laser write beam (26).

Description

Technical Field

[0001] The invention relates to a method for generating a three-dimensional structure and a laser lithography apparatus. Background Art

[0002] The laser lithography technique mentioned in this article is also referred to as, for example, stereolithography or direct laser writing. With this technique, a structure is written into a photosensitive substance, which is usually initially liquid, and which is referred to in this article as a photolithographic material, by means of a laser writing beam. In the process, a curing effect is triggered locally in the photolithographic material by the laser writing beam. For example, curing occurs due to local polymerization of the photolithographic material caused by photon absorption. In the field of optical lithography, such a photolithographic material is also called a photoresist. In the field of stereolithography, such a photolithographic material is also called a resin.

[0003] Laser lithography or direct laser writing is advantageously used for the production of micro- or nanostructures when high precision is required while maintaining freedom of design and flexibility of formation, for example, in contrast to mask lithography, that is, different structures can be written without specifying the structure via a mask or the like.

[0004] Various techniques are known which can lead to direct contact between the focusing optics or their optical terminal elements and the photolithographic material to varying degrees. Firstly, it is known in principle to produce a desired overall structure by sequentially writing a series of partial structures (e.g., layered or sliced), which then complement each other overall to form the desired structure.

[0005] In one known technique, the writing beam hits the surface of a volume of photoresist material and causes local solidification on the surface. Usually, these methods are based on linear processes, such as single-photon absorption and the resulting local changes in the photoresist material. In order to write structures that extend three-dimensionally, in this method, after writing one layer in an application step, an additional layer of photoresist material is applied. This can be achieved, for example, by gradually lowering the substrate with the structure to be written thereon into a bath of photoresist material, and each time structuring is carried out by the writing beam on the surface. In this technique, it can occur that the terminal elements of the focusing optics come into contact with the photoresist material.

[0006] Another method generally uses the physical principle of two-photon polymerization or multi-photon polymerization to achieve the curing of the lithographic material even within a certain volume of the lithographic material, that is, to achieve the curing of the lithographic material below the surface. This is possible for the writing beam and the lithographic material to coordinate with each other so that the curing effect occurs in the case of nonlinear effects. For example, the writing beam is selected within a spectral range that cannot usually trigger the curing effect in the lithographic material. For example, the lithographic material and the writing beam can be coordinated in such a way that the initiated curing occurs only when two or more photons of the writing beam are absorbed (two-photon polymerization or multi-photon polymerization). In this article, the term "multi-photon polymerization" means polymerization initiated by absorbing two or more photons. In this regard, the term "multi-photon absorption" also includes the processes of "two-photon absorption" and "two-stage absorption" used in this specification. The conditions required for multi-photon polymerization are generally only achieved in the region of increased intensity. The region of increased intensity is generally set in the region of the focus of the laser writing beam. In this regard, the focus is the beam waist of the laser writing beam generated by a suitable optical device (e.g., a beam guiding optical device, a beam shaping optical device and / or an objective lens). For the lithographic production of extended three-dimensional structures, the focal point can then be moved throughout the volume of the lithographic material according to the geometric description data and trigger the curing process locally.

[0007] The production of three-dimensional structures using two-photon polymerization is usually carried out at a working distance of 100 μm (micrometers) to 20 mm (millimeters). The working distance is the distance between the focal point and the optical terminal element of the objective lens used to produce the focal point. At such a small working distance, it is usually not possible to prevent the contact of the lens with the photolithographic material. In particular, the objective lens is immersed in the photolithographic material. The production method in which the lens is at least partially immersed in the photolithographic material can also be referred to as immersion multiphoton polymerization. Here, during the production of the three-dimensional structure, the photolithographic material frequently reaches the objective lens, in particular the optical terminal element.

[0008] Regardless of the specific technique used, one challenge is that the process of writing complex structures can be time consuming, and speeding up the process should generally not come at the expense of accuracy.

[0009] EP4163083A1 discloses a device for producing three-dimensional components based on photolithography. The device has a beam splitter for splitting an input beam into a plurality of beams focused on a focal point within a material. In addition, the device has a plurality of acousto-optic modulators corresponding to the number of beams. The acousto-optic modulator is arranged in each beam path to move the focal point of that particular beam. Summary of the invention

[0010] The invention is based on the object of achieving, in particular, rapid production of three-dimensional structures by utilizing laser lithography.

[0011] This object is achieved by a method having the features of claim 1 and by a laser lithography apparatus having the features of claim 8. Advantageous and preferred embodiments of the invention are contained in the dependent claims.

[0012] According to the present invention, the method for generating a three-dimensional structure in a photolithography material comprises the following steps: receiving the photolithography material by means of a photolithography material receiving portion; generating an input laser beam by means of a laser beam source, wherein the laser beam propagates along a propagation direction; demultiplexing the laser beam by means of a demultiplexing unit arranged between the laser beam source and an objective lens to form a plurality of, in particular three, four or five, laser writing beams; focusing the plurality of laser writing beams by means of an objective lens; and generating a three-dimensional structure in the photolithography material by means of the focused laser writing beam.

[0013] By demultiplexing the laser beam, a plurality of laser writing beams are generated, wherein a three-dimensional structure can then be generated by means of the plurality of laser writing beams. This reduces the time required to move the photolithographic material relative to the laser writing beams and thus enables the production of three-dimensional structures particularly quickly.

[0014] When two-photon polymerization or multiphoton polymerization is used, splitting the laser writing beam by time demultiplexing can bring particular advantages to laser lithography. The photolithographic material is converted into an exposed state due to nonlinear processes, in particular polymerized or cured. For this reason, when a pulsed laser beam is used, the peak power of the individual laser pulses of the laser beam is a relevant variable for the process of two-photon polymerization or multiphoton polymerization. By time demultiplexing of the laser beam, a laser writing beam is generated, which has a higher peak power than the laser writing beam generated by continuous beam splitting (for example, with the help of a beam splitter). Continuous beam splitting can be understood as continuous beam splitting in time or passive continuous beam splitting. Passive optical elements can be used to achieve continuous beam splitting. Therefore, time demultiplexing improves the process efficiency in two-photon polymerization or multiphoton polymerization.

[0015] The laser beam source can be designed as a laser diode.

[0016] The laser writing beam hits the photolithographic material or is focused into the photolithographic material. The laser writing beam and the photolithographic material can be coordinated with each other so that the photolithographic material can be locally converted into an exposed state, in particular polymerized or cured, in a specific focus of the laser writing beam or in a plurality of regions around a specific focus, so as to generate a three-dimensional structure by means of multiphoton polymerization.

[0017] The laser writing beam may pass through a frequency doubling device for doubling the frequency of the laser writing beam. The frequency doubling device may be arranged between the waveguide arrangement and the objective lens. The frequency doubling device may include a nonlinear crystal, such as a lithium niobate crystal. The nonlinear crystal may be arranged in phase with the laser writing beam so that at least a portion of each laser writing beam is frequency doubled after passing through the nonlinear crystal. The frequency doubling device may be held by a holding matrix.

[0018] The photolithography material receiving portion can be designed to receive photolithography material for generating a three-dimensional structure. In particular, the photolithography material receiving portion can receive a certain volume of photolithography material so that the laser writing beam can be focused into the photolithography material. The photolithography material receiving portion can receive the photolithography material so that the objective lens can be immersed in the photolithography material to generate a three-dimensional structure.

[0019] Preferably, the photolithographic material receiving portion is designed to hold the position of the photolithographic material for generating a three-dimensional structure. The photolithographic material receiving portion may be referred to as a photolithographic material carrier.

[0020] For the photolithographic material receiving part, various geometric designs are conceivable, each of which can bring different advantages. For example, the photolithographic material receiving part can be designed as a basin, container or tank for receiving the photolithographic material. It is also conceivable to design the photolithographic material receiving part as a platform or carrier or substrate, on which the photolithographic material is located in the form of drops or layers. In order to generate a three-dimensional structure on the substrate, it is also conceivable that the substrate, in particular a substrate in the form of a wafer, is placed on the platform and the photolithographic material is located on the substrate in the form of drops or layers. The platform can be a machining table of a lithographic apparatus.

[0021] The photolithographic material receiving portion can be designed to be transparent to the laser writing beam at least in certain areas. For example, if a wall or a base plate or a cover plate of the photolithographic material receiving portion is present in a particular design, it can be designed to be transparent to the laser writing beam. Thus, the laser writing beam can be focused through the photolithographic material receiving portion and enter the photolithographic material. For example, the photolithographic material can be irradiated or exposed from below.

[0022] The input laser beam may be a continuous wave laser beam or a pulsed laser beam. In particular, the laser pulses of the pulsed laser beam may have a pulse duration of 50 femtoseconds to 500 nanoseconds.

[0023] The demultiplexing of the input laser beam may be a temporal and / or spatial demultiplexing of the input laser beam. In particular, the temporal and spatial demultiplexing of the input laser beam may be achieved simultaneously. Preferably, demultiplexing the input laser beam may result in temporal and spatial segmentation of the input laser beam. The segmentation may be understood as deflection, orientation, decoupling or extraction. The segmentation may be achieved by an optical switch. The optical switch may be a fiber integrated optical switch.

[0024] In this respect, the method in particular provides for forming a plurality of laser writing beams by demultiplexing the laser beam by means of a demultiplexing unit arranged between the laser beam source and the objective lens. In particular, demultiplexing is the opposite of multiplexing. Demultiplexing may comprise directing or guiding at least part of the power of the input laser beam to one of a plurality of outputs of the demultiplexing unit. At least part of the power of the input laser beam directed or guided to the output may form the laser writing beam after passing through the output. Demultiplexing may comprise directing or guiding at least part of the power of the input laser beam alternately to mutually different outputs of the demultiplexing unit.

[0025] If the input laser beam is a pulsed laser beam, the demultiplexing may be a pulse picking of individual laser pulses or groups of laser pulses of the pulsed input laser beam. If the input laser beam is a continuous wave laser beam, the demultiplexing may be a formation of a pulsed laser writing beam, wherein, in particular, the pulse width and / or the pulse length is equal to the switching duration of the demultiplexing unit. For example, duty cycle pulses may be generated by the demultiplexing unit. In other words, the continuous wave laser beam may be put into pulse form using the demultiplexing unit.

[0026] The demultiplexing of the input laser beam can be performed constantly, periodically or according to a signal over time. For example, the demultiplexing can be performed so that each laser writing beam is formed from the input laser beam within a specified time period. The specified time period can be, for example, 100 femtoseconds to 500 nanoseconds.

[0027] Each laser writing beam may propagate along a beam axis. The beam axes of the laser writing beams may be different from each other. The beam axes of the laser writing beams may be parallel to each other and offset from each other. The beam axis of the laser writing beam and the beam axis of the input laser beam may be different from each other, in particular the beam axis of the input laser beam may be oriented perpendicular to the beam axis of the laser writing beam. In other words, the beam axis of the laser writing beam cannot be colinear with the beam axis of the laser beam.

[0028] The beam axis may be understood as the longitudinal axis of a particular laser beam extending in its propagation direction. In this regard, the beam axis may be defined by the Poynting vector of the radiation. The Poynting vector may be an effective Poynting vector. For example, the effective Poynting vector may be an intensity-weighted average Poynting vector.

[0029] Each laser writing beam may be designed to transform the photoresist material into an exposed state by two-photon or multi-photon polymerization, in particular to polymerize or cure the photoresist material in another manner.

[0030] Focusing the plurality of laser writing beams may comprise forming a plurality of focal points. In particular, all the laser writing beams are focused using the same objective lens, in particular focused such that each laser writing beam has its own, specified focal point. The focal points may be separated from each other spatially and temporally. In other words, the plurality of laser writing beams may be focused such that the laser writing beams form focal points sequentially in time and spatially adjacent to each other. Preferably, the arrangement is such that the focal points are located within the volume of the lithographic material, preferably below the surface of the lithographic material.

[0031] In conjunction with the step of focusing the plurality of laser writing beams, the method may comprise the step of immersing the objective lens in the photolithographic material, in particular before focusing. In other words, the method may be an immersion multiphoton polymerisation method.

[0032] For example, the objective lens may have a numerical aperture in the range from 0.01 to 1.6 (inclusive). In particular, a high numerical aperture may contribute to high precision.

[0033] Generating a three-dimensional structure in the photolithographic material may include spatially superimposing the focus of the laser writing beam with the photolithographic material. In other words, in order to generate the three-dimensional structure, the laser writing beam is focused into the photolithographic material. The three-dimensional structure in the photolithographic material may be generated using multiphoton polymerization of the photolithographic material.

[0034] In a further development of the method, the demultiplexing comprises forming each laser writing beam by decoupling from the input laser beam a portion of the laser beam sufficient to transform the photolithographic material into an exposed state. In particular, the decoupling can be achieved so that a specific laser writing beam has at least an exposure dose, energy dose and / or intensity at its focus sufficient for two-photon or multi-photon polymerization of the photolithographic material. The exposure can be done by two-photon or multi-photon polymerization.

[0035] For example, the photoresist material may be liquid in an unexposed state and solid in an exposed state. In other words, the photoresist material may be locally solidified by locally converting the photoresist material into an exposed state. Then, for example, in the development step herein, the unexposed liquid photoresist material may be separated from the photoresist material solidified due to exposure.

[0036] In an alternative embodiment, the photoresist material may be solid in an unexposed state, and in an exposed state, the structure of the photoresist material, such as the chemical structure, molecular structure, crosslinking, degree of polymerization, etc. of the photoresist material, may be changed compared to the unexposed state. In other words, the photoresist material may be locally transformed into an exposed state by changing the crosslinking of the photoresist material. The unexposed photoresist material may then be separated from the exposed photoresist material, for example in a development step.

[0037] In a further development of the method, the input laser beam is a pulsed laser beam having a plurality of laser pulses. The plurality of laser writing beams are formed by decoupling a first group of laser pulses and at least a second group of laser pulses from the pulsed input laser beam. The first group of laser pulses forms the first laser writing beam and the second group of laser pulses forms the second laser writing beam. The first group of laser pulses and the second group of laser pulses may be separated from each other in time and space. The decoupling may be referred to as pulse picking.

[0038] In a further development of the method, the method comprises: after demultiplexing, detecting the power of the input laser beam in the beam path of the input laser beam. The formation of the plurality of laser writing beams is performed in dependence on the detected power. Detecting the power may be detecting the power of a residual beam of the input laser beam. The residual beam is preferably not a laser writing beam. In particular, the residual beam may be a laser beam remaining from the input laser beam after demultiplexing the input laser beam. The demultiplexing may be performed by a demultiplexing unit. The power may be detected downstream of the demultiplexing unit. The power may be the power of the input laser beam after passing through the demultiplexing unit.

[0039] In a further development of the method, the method has the step of coupling a plurality of laser writing beams into a waveguide arrangement having a plurality of waveguides. One waveguide is correspondingly assigned to one laser writing beam. The waveguide is arranged in the beam path between the laser beam source and the objective lens. With the aid of the waveguide arrangement, the method can advantageously be carried out in a particularly stable and reliable manner. The waveguide arrangement can produce a defined spatial arrangement of the laser writing beams relative to each other and maintain this spatial arrangement robustly against interference. Each waveguide can be designed to guide or direct a specific laser writing beam. Each waveguide can be designed as a hollow core fiber or a solid core fiber or include one.

[0040] In a further development of the method, each waveguide has a first end and a second end opposite to the first end. Each first end is configured to couple a laser writing beam, and each second end is configured to decouple the laser writing beam coupled to the first end. The second ends of the plurality of waveguides are held by a holding matrix of the waveguide arrangement. The method may include moving the focus relative to the photolithographic material receiving portion by moving the holding matrix. If necessary, the waveguide can move with the movement of the holding matrix, for example, by corresponding (elastic) deformation, bending, etc. The movement of the focus relative to the photolithographic material receiving portion can also be achieved or supported by moving the objective lens. As an alternative or supplement to the above options, the focus is moved relative to the photolithographic material receiving portion by moving the photolithographic material receiving portion and / or using an optical deflection device to deflect the laser writing beam.

[0041] The provision of the holding matrix enables the second ends of the waveguides to be held in a defined arrangement relative to one another in a particularly compact and precise manner.

[0042] The holding matrix may be made of plastic, resin, glass or silicon, wherein the second end of the waveguide is at least partially, in particular partially, embedded therein.

[0043] The retention matrix may include a substrate with finely machined V-shaped notches for insertion of the waveguides. Alternatively, the retention matrix may have a microstructured perforated plate into the holes of which the waveguides may be inserted. Alternatively, the retention matrix may have a plurality of ferrules into which the waveguides may be inserted. Alternatively, the retention matrix may be a soldered connection between the second ends of the waveguides of the waveguide arrangement.

[0044] A movement can be understood as a performance of a movement. Each movement can be performed by a drive, in particular a linear drive and / or a rotary drive.

[0045] The movement of the holding matrix can be achieved by moving the holding matrix transversely to the laser writing beam and / or by moving the holding matrix longitudinally relative to the laser writing beam.

[0046] During the movement of the focal point relative to the lithographic material receiving part by moving the holding matrix, the objective lens can be stationary or can move together with the holding matrix. The movement of the holding matrix together with the objective lens can mean that the holding matrix and the objective lens move the same distance in the same direction at the same time. The joint movement of the holding matrix and the objective lens can be achieved, for example, by means of the same drive.

[0047] During the movement of the focal point relative to the lithographic material receiving part by moving the lithographic material receiving part, the holding matrix and / or the objective lens may be stationary.

[0048] The optical deflection device can be arranged between the waveguide arrangement and the objective lens.The optical deflection device can have a scanning mirror, a mirror galvanometer, an acousto-optic deflector, an acousto-optic modulator and / or a membrane mirror for deflecting the laser writing beam.

[0049] In a further development of the method, each waveguide is designed as a hollow core fiber. This ensures that unwanted absorption is significantly reduced and the damage threshold of the waveguide is significantly higher. Furthermore, each hollow core fiber can be matched to its associated laser writing beam so that the laser pulses of the laser writing beam do not experience pulse broadening after passing through the hollow fiber. A hollow core fiber can be an optical fiber with a hollow fiber core.

[0050] In a further development of the method, each waveguide is selected from the group comprising: hollow core photonic crystal fiber (HC PCF fiber), in particular hollow core kagome fiber (HC kagome fiber), hollow core photonic bandgap fiber (HC PBGF fiber), hollow core anti-resonance fiber (HC ARF fiber), hollow core suppressed coupling fiber (HC IC fiber), radiation-resistant fiber (RH fiber), large mode area fiber (LMA fiber), photonic crystal fiber (PCF fiber).

[0051] HC PCF fiber can be understood as hollow-core photonic crystal fiber, HC kagome fiber can be understood as hollow-core kagome fiber, HCPBGF fiber can be understood as hollow-core photonic bandgap fiber, HC ARF fiber can be understood as hollow-core anti-resonant fiber, HC IC fiber can be understood as hollow-core inhibited coupling fiber, RH fiber can be understood as radiation-hardened fiber, LMA fiber can be understood as large mode area fiber, and PCF fiber can be understood as photonic crystal fiber.

[0052] A laser lithography device for generating a three-dimensional structure in a photolithography material according to the present invention. To some extent, since the features and components of the laser lithography device are also described in conjunction with the method, the statements in this regard are also applicable to the laser lithography device accordingly. The device has a photolithography material receiving portion, a laser beam source, a multiplexing unit, an objective lens and a scanning device. The photolithography material receiving portion is designed to receive the photolithography material. The laser beam source is designed to generate an input laser beam. The multiplexing unit is arranged between the laser beam source and the objective lens, in particular, along the propagation direction of the input laser beam. The multiplexing unit is configured to temporally split the input laser beam into a plurality of laser writing beams by multiplexing. The objective lens is designed to focus the laser writing beam on a focus corresponding to each laser writing beam. The scanning device is designed to move the focus relative to the photolithography material receiving portion.

[0053] The laser lithography apparatus is particularly designed and specifically configured to perform the above method.The description of the above method is equally applicable to the same or functionally equivalent features in the laser lithography apparatus.

[0054] The scanning device may have an optical deflection device as described previously for moving the focal point relative to the lithographic material receiving portion by deflecting the laser writing beam. The optical deflection device of the scanning device may be arranged between the demultiplexing unit and the objective lens.

[0055] Additionally or alternatively, the scanning device can be designed to move the focus relative to the photolithographic material receiving part by moving the objective lens and / or to move the focus relative to the photolithographic material receiving part by moving the photolithographic material receiving part. For the movement, the scanning device can here include an actuator, in particular a servomotor or a linear actuator, preferably a vibrating piezoelectric actuator.

[0056] The photolithographic material may be received by the photolithographic material receiving part. The photolithographic apparatus may further include the photolithographic material.

[0057] In a further development of the laser lithography apparatus, the laser beam source is designed to generate a pulsed input laser beam having a plurality of laser pulses. The demultiplexing unit is designed to demultiplex by decoupling a first group of laser pulses and at least a second group of laser pulses from the pulsed input laser beam. The first group of laser pulses forms the first laser writing beam and the second group of laser pulses forms the second laser writing beam.

[0058] In a further development of the laser lithography apparatus, the demultiplexing unit has a plurality of, in particular three, four or five, optical switches, which are arranged in series in the beam path of the input laser beam. Each optical switch is configured in a switched position to form a corresponding laser writing beam by decoupling a portion of the laser beam sufficient to convert the lithographic material into an exposed state from the input laser beam. In particular, in an unswitched position, the laser writing beam is not decoupled. Each optical switch can be designed as a fiber-integrated optical switch.

[0059] The optical switches can be arranged in series in the propagation direction of the input laser beam. A plurality of optical switches can be equal to a plurality of laser writing beams. Providing an optical switch can correspondingly form a laser writing beam.

[0060] Each optical switch may have an acousto-optic modulator or an acousto-optic deflector for decoupling a portion of the laser beam sufficient to convert the photolithographic material into an exposed state from the input laser beam. Each optical switch may have a digital input terminal for switching the optical switch to a switched position. A signal may be applied to the digital input terminal to move the optical switch between a switched position and an unswitched position. For example, when a signal is applied to the digital input terminal, the optical switch may be in a switched position, and when no signal is applied to the digital input terminal, the optical switch may be in an unswitched position.

[0061] When the optical switch is in the unswitched position, in particular, the input laser beam can pass through the optical switch without forming a laser writing beam.

[0062] It is conceivable that the degree of decoupling of each optical switch is adjustable, in particular infinitely variable. The degree of decoupling of the optical switch can be the relationship between the power (in particular the peak power or the average power) of the laser writing beam formed by the optical switch relative to the power (in particular the peak power or the average power) of the input laser beam upstream of the optical switch. In the unswitched position, the degree of decoupling can be 0%. In other words, when the degree of decoupling is 0%, the input laser beam can pass through the optical switch without forming a laser writing beam. In the switched position, the degree of decoupling can be, for example, 10%, 20%, 30%, 40%, 50%, 60%, 80%, 90% or 95%. In other words, when the optical switch is continuously in the switched position, the power of the laser writing beam formed by the optical switch is 10%, 20%, 30%, 40%, 50%, 60%, 80%, 90% or 95% of the power of the input laser beam upstream of the optical switch.

[0063] The optical switch may have an analog input to which a signal may be applied in order to adjust the degree of decoupling. By adjusting the degree of decoupling, different exposure levels of the photolithographic material may be achieved.

[0064] In a further development of the laser lithography apparatus, the demultiplexing unit has an optical switch which is arranged in the beam path of the input laser beam downstream of the laser beam source. The demultiplexing unit has an optical arrangement which is configured to guide the input laser beam through the optical switch a plurality of times. In the switched position, the optical switch is configured to form the laser writing beam from the input laser beam by decoupling a portion of the laser beam which is sufficient to transform the lithographic material into an exposed state.

[0065] In particular, the demultiplexing unit may have a single optical switch. The optical arrangement may be configured to cause the input laser beam to pass through the optical switch two, three or four times. The optical arrangement may be configured to direct the input laser beam to pass through the optical switch multiple times at different incident angles. The above description of the optical switch also applies to the optical switch through which the input laser beam passes multiple times.

[0066] In a further development of the laser lithography apparatus, the laser lithography apparatus has a power detection unit for detecting the power of the input laser beam in the beam path after the demultiplexing unit. The laser lithography apparatus has a control unit configured to control the demultiplexing unit in dependence on the detected power so as to form a plurality of laser writing beams by demultiplexing the input laser beam. The control unit may be a computer or a computing unit.

[0067] The power detection unit may be a photodiode or a power detector for detecting the power of the input laser beam. The power detection unit may be arranged so that the power detection unit detects the power of a residual beam of the input laser beam. The residual beam may not be a laser writing beam. The residual beam may be a laser beam remaining from the input laser beam after the input laser beam passes through the demultiplexing unit. The power may be the power of the residual beam.

[0068] In a further development of the laser lithography apparatus, the laser lithography apparatus has a waveguide arrangement having a plurality of waveguides for guiding a plurality of laser writing beams. One waveguide is correspondingly assigned to one laser writing beam. The waveguides in the beam path are arranged between the demultiplexing unit and the objective lens. Each waveguide has a first end and a second end opposite to the first end. Each first end is configured to couple a laser writing beam, and each second end is configured to decouple the laser writing beam coupled into the first end. The second ends of the plurality of waveguides are held by a holding matrix of the waveguide arrangement. Within the holding matrix, the waveguides may be parallel to each other and deviate from each other. Each waveguide may be formed as a hollow core fiber or a solid core fiber, or may include a corresponding optical fiber.

[0069] The second ends may be spaced apart from each other in the propagation direction of the laser writing beam coupled out from the second ends. In other words, each second end of the plurality of waveguides may have an end face configured to decouple the laser writing beam coupled into the first end, wherein the end faces of the second ends are arranged in planes different from each other. In other words, the second ends extend for different distances. Advantageously, this enables simultaneous exposure of photolithographic materials in different planes. This can increase the stability of the three-dimensional structure during the generation or printing process. In addition, the three-dimensional structure can be generated faster. In particular, this can achieve a higher packing density of the focus.

[0070] In a further development of the laser lithography apparatus, the second ends of the plurality of waveguides are held in a linear arrangement or a two-dimensional arrangement by a holding matrix. The linear arrangement and / or the two-dimensional arrangement may be a regular arrangement.

[0071] If the second ends are kept in a linear arrangement, the second ends may be equidistant from each other. If the second ends are kept in a two-dimensional arrangement, the second ends may be arranged in a crystal-like structure. A crystal-like structure may be understood to mean that the second ends are arranged like a dot matrix with a periodically repeating pattern.

[0072] In a further development of the laser lithography apparatus, the distance between two adjacent second ends of the plurality of waveguides is 25 μm to 1000 μm, in particular 115 μm to 600 μm. This enables a particularly compact waveguide arrangement.

[0073] In a further development of the laser lithography apparatus, each second end of the plurality of waveguides has an end face configured to decouple the laser writing beam coupled into the first end. The end faces of the second ends are arranged in a plane. The plane may be perpendicular to the propagation direction of the coupled-out laser writing beam.

[0074] In a further development of the laser lithography apparatus, the scanning device is configured to move the focal point relative to the lithographic material receiving portion by means of moving the holding matrix. To this end, the scanning device may comprise an actuator, in particular a servomotor or a linear motor that moves the holding matrix.

[0075] In a further development of the laser lithography apparatus, each waveguide is designed as a hollow-core optical fiber.

[0076] In a further development of the laser lithography apparatus, each waveguide is selected from the group comprising: hollow core photonic crystal fiber, in particular hollow core Kagome fiber, hollow core photonic bandgap fiber, hollow core anti-resonance fiber, hollow core suppressed coupling fiber, radiation-resistant fiber, large mode area fiber, photonic crystal fiber. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Further advantages and aspects of the invention emerge from the claims and the following description of preferred exemplary embodiments of the invention, which are explained below with reference to the accompanying drawings. Identical and functionally corresponding elements have the same reference numerals. In the drawings:

[0078] Figure 1 shows a schematic diagram of a laser lithography apparatus;

[0079] Figure 2 A schematic diagram showing the operation of a demultiplexing unit of a laser lithography apparatus;

[0080] Figure 3 A schematic diagram showing the front side of a waveguide arrangement of a laser lithography apparatus;

[0081] Figure 4 Shows Figure 3 Schematic diagram of a variation of the waveguide arrangement;

[0082] Figure 5 A schematic diagram showing the focus of the laser writing beam in the focal plane;

[0083] Figure 6 The plane perpendicular to the focal plane is shown. Figure 5 A schematic diagram of the focal point of

[0084] Figure 7 Shows Figure 1 Schematic diagram of a variation of a laser lithography apparatus. DETAILED DESCRIPTION

[0085] Figure 1 A laser lithography apparatus 10 for producing three-dimensional structures in a lithographic material 12 by means of multiphoton polymerization is shown.

[0086] The laser lithography apparatus 10 has a lithography material receiving part 14. The lithography material receiving part 14 is designed as a workbench in the form of a machining workbench. A substrate 16 in the form of a wafer is placed on the lithography material receiving part 14, and a three-dimensional structure is to be generated on the substrate 16.

[0087] The photoresist material 12 is located in the form of droplets on the photoresist material receiving portion 14 and on the substrate 16 . Figure 1 The photoresist material 12 is shown contacting the photoresist material receiving part 14 and the substrate 16. In an alternative embodiment (not shown), the photoresist material contacts only the substrate. In both cases, the photoresist material receiving part 14 is designed to receive the photoresist material 12 for use in generating a three-dimensional structure.

[0088] The laser lithography apparatus 10 has a laser beam source 18 for generating an input laser beam 20. The input laser beam 20 propagates along a propagation direction 22.

[0089] The input laser beam 20 is a pulsed laser beam including a plurality of laser pulses. The laser pulses of the pulsed input laser beam 20 have a pulse duration of 250 femtoseconds. The laser pulses of the pulsed input laser beam 20 have a repetition rate of 80 MHz.

[0090] The laser lithography apparatus 10 has a demultiplexing unit 24. The demultiplexing unit 24 is arranged after the laser beam source 18 along the propagation direction 22 of the input laser beam 20. The demultiplexing unit 24 is configured to split the input laser beam 20 into a plurality of laser writing beams 26 in time and space by demultiplexing.

[0091] Each laser writing beam 26 propagates along a beam axis. The beam axis is the longitudinal axis of a particular laser writing beam 26, and the beam axis extends along the propagation direction of the laser writing beam 26. The beam axes of the laser writing beams 26 are different from each other. The beam axes of the laser writing beams 26 are oriented parallel to each other and offset from each other. The beam axes of the laser writing beams 26 and the beam axis of the input laser beam 20 are oriented orthogonally to each other. In other words, the beam axis of the laser writing beam 26 is not colinear with the beam axis of the laser beam 20.

[0092] exist Figure 1 In the example shown, the input laser beam 20 is split by the demultiplexing unit 24 into a total of four laser writing beams 26. For this purpose, the demultiplexing unit 24 has a total of four optical switches 28, which are arranged in series one after the other in the propagation direction 22. In other words, in the unswitched position of the optical switches 28, the input laser beam 20 can pass through the optical switches 28 one after the other without being influenced by the optical switches 28.

[0093] One optical switch 28 is used to form one laser writing beam 26 accordingly. Each optical switch 28 is configured in the switching position to form a corresponding laser writing beam 26 from the input laser beam 20. Each optical switch 28 is designed as an acousto-optic modulator. The laser writing beam 26 is formed by decoupling a portion of the laser beam sufficient to cure the photolithographic material 12 from the input laser beam 20. In other words, demultiplexing is to direct or guide a sufficient portion of the laser beam to one of the multiple outputs 29 of the demultiplexing unit 24. In the exemplary embodiment shown, this is achieved by means of the optical switch 28 and a deflection mirror (not shown for simplicity).

[0094] In general, the demultiplexing unit 24 has four outputs 29. The number of outputs 29 is equal to the number of laser writing beams 26 formed by the demultiplexing unit 24. A sufficient portion of the laser beam directed or guided to the output 29 forms the laser writing beam 26 after passing through the output 29.

[0095] In order to form four laser writing beams 26 by means of the demultiplexing unit 24 , the optical switches 28 are successively switched into the switching position, which then decouple a sufficient portion of the laser beam from the input laser beam 20 and direct it to the associated output 29 .

[0096] Each optical switch 28 has a digital input for switching the optical switch between an unswitched position and a switched position. The switching to the switched position or to the unswitched position is performed by means of a signal applied to the digital input. In the example shown, when a signal is applied to the digital input, the optical switch 28 is in the switched position, and when a signal is not applied to the digital input, the optical switch 28 is in the unswitched position.

[0097] The laser lithography apparatus 10 has a control unit 30 configured to control the demultiplexing unit 24 so as to form a laser writing beam 26 by demultiplexing the input laser beam 20. The optical switches 28 are switched sequentially to a switching position by the control unit 30. To this end, the control unit 30 applies a signal to a digital input terminal of each optical switch 28 sequentially.

[0098] The laser lithography apparatus 10 has a power detection unit 32 in the form of a power detector for detecting the power of the input laser beam 20 downstream of the demultiplexing unit 24. Thus, the power detection unit 32 detects the power of the input laser beam 20 remaining after the input laser beam 20 passes through the demultiplexing unit 24. Figure 1In the example shown, the power detection unit 32 is arranged such that the input laser beam 20 hits the power detection unit 32 when the optical switch 28 is in the unswitched position and the input laser beam 20 passes through the optical switch 28 in sequence without being affected by the optical switch 28. The power detection unit 32 detects the power of the input laser beam 20, which is equal to the power of the input laser beam 20 upstream of the demultiplexing unit 24.

[0099] If one of the optical switches 28 is in the switched position and, for example, 80% of the peak power of the input laser beam 20 is decoupled to form the laser writing beam 26, the power detection unit 32 will detect the power of the input laser beam 20, wherein the peak power of the input laser beam 20 hitting the power detection unit 32 is 20% of the peak power of the input laser beam 20 upstream of the demultiplexing unit 24.

[0100] The control unit 30 is configured to control the demultiplexing unit 24 according to the power detected by the power detection unit 32 .

[0101] An example of the operation of the demultiplexing unit 24 is shown in Figure 2 Shown in.

[0102] exist Figure 2 In a), individual laser pulses 34 of the pulsed input laser beam 20 upstream of the demultiplexing unit 24 are shown in the form of arrows on a time axis 36. Figure 2 In b) to e) of the drawings, the time course of the signal applied by the control unit 30 to the digital input of the respective optical switch 28 is shown on the time axis 36. When the signal has the value 1, the respective optical switch 28 is in the switched position, and when the signal has the value 0, the respective optical switch 28 is in the non-switched position.

[0103] The control unit 30 is configured to apply signals to the digital inputs of the optical switches 28 in sequence for a specified duration. The specified duration is the same for all optical switches 28. Figure 2 In the exemplary embodiment of FIG. 2 , the specified duration is selected so that each optical switch 28 decouples ten laser pulses 34 from the input laser beam 20. In other words, the control unit 30 is configured to apply a signal for the duration of ten laser pulses 34 to the digital input of the optical switch 28. However, the specified duration may also be selected to be different so that more or fewer laser pulses 34 are decoupled. The decoupled laser pulses 34 at least partially form the laser writing beam 26.

[0104] Between two signals successively applied to the optical switch 28, no signal is applied to the optical switch 28 within a specified time period. Figure 2In the exemplary embodiment of the present invention, the specified time period is selected so that between the decoupled laser pulses 34, two laser pulses 34 are not decoupled by the optical switch 28. The undecoupled laser pulses 34 arrive at the power detection unit 32. However, the specified time period may also be selected to be different so that more or fewer laser pulses arrive at the power detection unit 32.

[0105] In detail, Figure 2 It is shown that two laser pulses 34 arrive at the power detection unit 32 in the time period 38. The control unit 30 sends the power detection unit 32 to the power detection unit 32 in the time period 40 including ten laser pulses 34. Figure 2 The signal shown in b) is applied to the first optical switch 28. The ten laser pulses 34 decoupled by means of the first optical switch 28 at least partially form the first laser writing beam 26. Subsequently, two laser pulses 34 in a time period 42 arrive at the power detection unit 32. The control unit 30 sets the ten laser pulses 34 in the time period 44 including the ten laser pulses 34 to the power detection unit 32. Figure 2 The signal shown in c) is applied to the second optical switch 28. The ten laser pulses 34 decoupled by the second optical switch 28 at least partially form the second laser writing beam 26. Then, the two laser pulses 34 in the time period 46 arrive at the power detection unit 32. The control unit 30 sets the second laser writing beam 26 to the power detection unit 32 in the time period 48 including the ten laser pulses 34. Figure 2 The signal shown in d) is applied to the third optical switch 28. The ten laser pulses 34 decoupled by the third optical switch 28 at least partially form the third laser writing beam 26. Then, the two laser pulses 34 in the time period 50 arrive at the power detection unit 32. The control unit 30 sets the ten laser pulses 34 in the time period 52 including the ten laser pulses 34 to the power detection unit 32. Figure 2 The signal shown in e) is applied to the fourth optical switch 28. The ten laser pulses 34 decoupled by means of the fourth optical switch 28 at least partially form the fourth laser writing beam 26. With the following two laser pulses 34, the sequence of applying the signal to the optical switch 28 starts again.

[0106] The calibration of the optical switches 28, in particular the calibration of the time deviation for the operation of the optical switches 28, is performed by applying a periodic signal to two optical switches 28 respectively, while no signal is applied to the remaining optical switches 28. Thereafter, the time deviation between the two periodic signals is changed, and at the same time, the average power is detected by means of the power detection unit 32. In this case, when the two optical switches 28 are in the switching position at the same time, the maximum average power is detected in the power detection unit 32. The time deviation in this state can be used to determine whether the two optical switches 28 are in the switching position. Figure 2 The remaining optical switches 28 are calibrated accordingly.

[0107] The demultiplexing unit 24 is designed so that demultiplexing is performed by decoupling groups of laser pulses from the pulsed input laser beam 20. The groups of laser pulses form the laser writing beam 26. In other words, the demultiplexing unit 24 forms the laser writing beam 26 by pulse picking. The laser writing beam 26 is formed by splitting the laser pulses 34 of the input laser beam 20 in time and space.

[0108] The optical switches 28 each have an analog input to which a signal can be applied to set the degree of decoupling. The degree of decoupling of each optical switch 28 can be infinitely variably adjusted. The degree of decoupling is the relationship of the peak power of the laser writing beam 26 formed by the optical switch 28 relative to the peak power of the input laser beam 20 upstream of the optical switch 28.

[0109] The control unit 30 is configured to apply a signal for adjusting the degree of decoupling to the corresponding optical switch 28. In the example shown, the control unit 30 applies a signal to the analog input terminal so that the degree of decoupling is 80%. In other words, the peak power of the laser pulse decoupled by the optical switch 28 is reduced by 20% compared to the peak power of the laser pulse of the input laser beam 20.

[0110] See also Figure 1 , the laser lithography apparatus 10 has a waveguide arrangement 54. The waveguide arrangement 54 has a plurality of waveguides 56 for guiding a plurality of laser writing beams 26. One waveguide 56 is assigned to one laser writing beam 26, respectively.

[0111] The waveguides 56 are arranged in the beam path downstream of the demultiplexing unit 24. Each waveguide 56 is a hollow core fiber, ie a hollow core photonic crystal fiber. Each waveguide 56 is designed to guide or direct the laser writing beam 26 associated with the waveguide 56.

[0112] Each waveguide 56 has a first end 58 and a second end 60 opposite the first end. Each first end 58 is configured to couple a laser writing beam 26 associated with the waveguide 56. The laser writing beam 26 is coupled into the waveguide 56 by free space beam coupling. Each second end 60 has an end face that is configured to decouple the laser writing beam 26 coupled into the first end 58. Therefore, each second end 60 is configured to decouple the laser writing beam 26 coupled into the first end 58.

[0113] The second end 60 is held by a holding matrix 62 of the waveguide arrangement 54. Within the holding matrix 62, the waveguides 56 are parallel to each other and offset from each other. In the example shown, the holding matrix 62 has a substrate with finely machined parallel V-shaped notches. The substrate can be made of, for example, plastic, resin, glass or silicon. The waveguides 56 are inserted into the notches. The free space between the waveguides 56 and the substrate is filled with an adhesive suitable for optical devices, for example in the form of a UV adhesive. The cover of the holding matrix 62 is glued on, pressing the waveguides 56 into the V-shaped notches.

[0114] The end surface of the second end 60 is arranged in a plane. The plane and the end surface 64 are arranged perpendicular to the propagation direction of the coupled-out laser writing beam 26.

[0115] Figure 3 A schematic diagram of an end face 64 of a waveguide arrangement 54 is shown. The second ends 60 of the waveguides 56 are held in a regular linear arrangement by a holding matrix 62. In other words, the second ends 60 have the same distance 66 from each other. The distance 66 between two adjacent second ends 60 is 250 μm.

[0116] Figure 4 Shows Figure 3 Another exemplary embodiment of a waveguide arrangement 54 is provided, which is suitable for up to eight laser writing beams. The same reference numerals are used for identical and functionally equivalent elements, and in this respect reference may be made to the description of the embodiments of the present invention. Figure 3 The above description of exemplary embodiments of the present invention is such that essentially only the differences that exist are explained.

[0117] Figure 4 The second ends 60 of the waveguide arrangement 54 are maintained in a regular two-dimensional arrangement by the holding matrix 62. The second ends 60 are arranged in a crystal-like structure. In other words, the second ends 60 are arranged in a periodic repeating pattern.

[0118] Figure 1 The lithographic apparatus 10 is shown with an optical deflection device 68 in the form of a mirror galvanometer and an objective lens 70 in the beam path of the laser writing beam 26 downstream of the waveguide arrangement 54. The optical deflection device 68 is designed to deflect the laser writing beam 26 and the objective lens 70 is designed to focus the laser writing beam 26.

[0119] The objective lens 70 is immersed in the photolithographic material 12. The objective lens 70 focuses the laser writing beam 26 for generating three-dimensional structures in the photolithographic material 12. The focal points of the laser writing beam 26 are all located in one focal plane.

[0120] Figure 5 Schematic diagram of the focal plane and each focal point 72. By demultiplexing the input laser beam 20, focal points 72 separated from each other in time and space are formed in the photolithographic material 12. Figure 5 This is shown by the dotted and solid lines of the focus 72 .

[0121] Figure 6 yes Figure 5 Schematic diagram of the focal point 72 of the laser writing beam in a plane orthogonal to the focal plane 74. A region 76 around the focal point of the laser writing beam is shown in which the photolithographic material 12 is cured by multiphoton polymerization. The laser writing beam 26 formed by demultiplexing thus has a portion of the laser beam from the input laser beam 20 sufficient to cure the photolithographic material 12.

[0122] Figure 1 The lithographic apparatus 10 is shown with a scanning device 78 for moving the focal point 72 relative to the lithographic material receiving part 14. The scanning device 78 comprises an optical deflection device 68. In addition, the scanning device 78 has an actuator 80 arranged on the lithographic material receiving part 14, an actuator 82 arranged on the objective lens 70 and an actuator 84 arranged on the holding matrix 62. Each actuator 80, 82, 84 is a linear actuator in the form of a piezoelectric actuator. In alternative embodiments (not shown), other actuator types are also conceivable.

[0123] In an alternative exemplary embodiment (not shown), the lithographic apparatus 10 may have at least one of the actuators 80 , 82 , 84 .

[0124] By means of an actuator 80 arranged on the photolithographic material receiving part 14, the scanning device 78 can move the focal point 72 relative to the photolithographic material receiving part 14 by moving the photolithographic material receiving part 14. By means of an actuator 82 arranged on the objective lens 70, the scanning device 78 can move the focal point 72 relative to the photolithographic material receiving part 14 by moving the objective lens 70. By means of an actuator 84 arranged on the holding matrix 62, the scanning device 78 can move the focal point 72 relative to the photolithographic material receiving part 14 by moving the holding matrix 62. By means of the optical deflection device 68, the scanning device 78 can move the focal point 72 relative to the photolithographic material receiving part 14 by moving the laser writing beam 26.

[0125] The laser lithography apparatus 10 is designed to perform a method for generating a three-dimensional structure in a lithographic material 12. The method comprises the following steps: receiving the lithographic material 12 using the lithographic material receiving part 14; generating an input laser beam 20 by means of a laser beam source 18; forming four laser writing beams 26 by demultiplexing the input laser beam 20 by means of a demultiplexing unit 62 arranged between the laser beam source 18 and an objective lens 70; coupling the plurality of laser writing beams 26 into a waveguide arrangement 54 having a plurality of waveguides 56; immersing the objective lens in the lithographic material; focusing the plurality of laser writing beams 26 into the lithographic material 12 by means of the objective lens 70; generating a three-dimensional structure in the lithographic material 12 by means of the focused laser writing beams 26 by multiphoton polymerization.

[0126] Figure 7 Shows Figure 1 Another exemplary embodiment of a laser lithography apparatus 10 of the present invention, wherein the same reference numerals are used for identical and functionally equivalent elements, and in this respect, reference may be made to the description concerning Figure 1 The above description of exemplary embodiments of the invention is such that essentially only the differences that exist are discussed.

[0127] The laser lithography apparatus 10 has an additional laser beam source 86. The additional laser beam source 86 is designed to generate a continuous wave laser beam.

[0128] In an alternative exemplary embodiment (not shown), the additional laser beam source may be designed to generate a pulsed laser beam.

[0129] exist Figure 7 In the exemplary embodiment of the embodiment of the present invention, the additional laser beam source 86 is coupled to the waveguide 56 of the waveguide arrangement 54. In other words, the additional laser beam source 86 provides its generated laser beam at a fiber output end coupled to the first end of the waveguide 56 of the waveguide arrangement 54. In order to couple the generated laser radiation, the fiber output end may be merged to the first end of the waveguide 56. Alternatively, the fiber output end and the first end of the waveguide 56 may be held by a coupler in order to couple the generated laser radiation into the first end.

[0130] The additional laser beam source 86 may have an integrated power modulation. The integrated power modulation may be realized, for example, by means of an integrated acousto-optic modulator. Alternatively, the additional power beam source 86 may modulate its power by electrical switching, for example by being alternately switched on and off. Alternatively, the additional power beam source 86 may be modulated by direct modulation, for example by electrically switching a supply current.

[0131] Figure 7The demultiplexing unit 24 of the laser lithography apparatus 10 has three optical switches 28, each of which generates a laser writing beam 26 by demultiplexing the input laser beam 20. The three laser writing beams 26 are coupled into the remaining three waveguides 56 of the waveguide arrangement 54 via free-space beam coupling.

Claims

1. A method for generating a three-dimensional structure in a photolithographic material (12), wherein: The method comprises the following steps: receiving the photolithographic material (12) by means of a photolithographic material receiving portion (14), generating an input laser beam (20) by means of a laser beam source (18), demultiplexing the input laser beam (20) to form a plurality of laser writing beams (26) by temporally splitting the input laser beam (20), focusing the laser writing beam (26) by means of an objective lens (70), The three-dimensional structure is generated in the photolithographic material (12) by means of the focused laser writing beam (26).

2. The method according to claim 1, wherein: Each laser writing beam (26) is formed by decoupling from the input laser beam (20) a portion of the laser beam sufficient to transform the photolithographic material (12) into an exposed state.

3. The method according to claim 1 or 2, wherein: The input laser beam (20) is a pulsed laser beam having a plurality of laser pulses (34), The input laser beam (20) is demultiplexed by decoupling a first group of laser pulses (34) and at least one second group of laser pulses (34) from the pulsed input laser beam (20), so that the first group of laser pulses (34) forms a first laser writing beam and the second group of laser pulses (34) forms a second laser writing beam.

4. A method according to any one of the preceding claims, wherein: The method comprises the following steps: After said demultiplexing, the power of said input laser beam (20) is detected in a beam path of said input laser beam (20), wherein said plurality of laser writing beams (26) are formed in dependence on said detected power.

5. A method according to any one of the preceding claims, wherein: The method comprises the following steps: The plurality of laser writing beams (26) are coupled into a waveguide arrangement (54), the waveguide arrangement (54) comprising a plurality of waveguides (56), wherein one waveguide (56) is respectively assigned to one laser writing beam (26), and wherein the waveguides (56) are arranged in the beam path between the laser beam source (18) and the objective lens (70).

6. The method according to claim 5, in, Each waveguide (56) has a first end (58) and a second end (60) opposite the first end (58), wherein each first end (58) is configured to couple a laser writing beam (26), and each second end (60) is configured to decouple the laser writing beam (26) coupled to the first end (58), wherein the second ends (60) of the plurality of waveguides (56) are retained by a retaining matrix (62) of the waveguide arrangement (54), Wherein, the method comprises the following steps: The focal point (72) is moved relative to the photolithographic material receiving portion (14) by moving the holding matrix (62), and / or The focal point (72) is moved relative to the photolithography material receiving portion (14) by moving the objective lens (70), The focal point (72) is moved relative to the photolithographic material receiving portion (14) by moving the photolithographic material receiving portion (14), and / or The focal point (72) is moved relative to the photolithographic material receiving portion (14) by deflecting the laser writing beam (26) by means of an optical deflection device (68).

7. The method according to claim 5 or claim 6, wherein: Each waveguide (56) is selected from the group consisting of: hollow core photonic crystal fiber, in particular hollow core Kagome fiber, hollow core photonic bandgap fiber, hollow core anti-resonance fiber, hollow core suppressed coupling fiber, radiation-resistant fiber, large mode area fiber, photonic crystal fiber.

8. A laser lithography apparatus (10) for generating a three-dimensional structure in a lithographic material (12), comprising: A photolithography material receiving portion (14), the photolithography material receiving portion (14) being used to receive the photolithography material (12); a laser beam source (18) for generating an input laser beam (20); a demultiplexing unit (24), the demultiplexing unit (24) being arranged between the laser beam source (18) and the objective lens (70), wherein the demultiplexing unit (24) is configured to temporally split the input laser beam (20) into a plurality of laser writing beams (26) by demultiplexing; an objective lens (70) for focusing the laser writing beam (26) to a focal point (72) corresponding to the laser writing beam (26); and A scanning device (78) is used to move the focus (72) relative to the photolithographic material receiving portion (14).

9. The laser lithography apparatus (10) according to claim 8, wherein: The laser beam source (18) is designed to generate a pulsed input laser beam (20) having a plurality of laser pulses (34), wherein the demultiplexing unit (24) is designed to perform the demultiplexing by decoupling a first group of laser pulses (34) and at least one second group of laser pulses (34) from the pulsed input laser beam (20), The first group of laser pulses (34) forms a first laser writing beam (26), and the second group of laser pulses (34) forms a second laser writing beam (26).

10. The laser lithography apparatus (10) according to claim 8 or 9, wherein: The demultiplexing unit (24) has a plurality of optical switches (28), and the plurality of optical switches (28) are sequentially arranged in series in the beam path of the input laser beam (20). Each optical switch (28) is configured in a switching position to form a corresponding laser writing beam (26) by decoupling a portion of the laser beam sufficient to convert the photolithographic material (12) into an exposed state.

11. The laser lithography apparatus (10) according to claim 8 or 9, wherein: The demultiplexing unit (24) comprises an optical switch (28) which is arranged in the beam path of the input laser beam (20) after the laser beam source (18), wherein the demultiplexing unit (24) has an optical arrangement configured to direct the input laser beam (20) through the optical switch (28) multiple times, The optical switch (28) is configured in the switching position to form a laser writing beam (26) by decoupling a portion of the laser beam sufficient to convert the photolithographic material (12) into an exposed state.

12. The laser lithography apparatus (10) according to any one of the preceding claims 8 to 11, in, The laser lithography device (10) comprises a power detection unit (32) for detecting the power of the input laser beam (20) in the beam path after the demultiplexing unit (24), The laser lithography device (10) comprises a control unit (30), wherein the control unit (30) is configured to control the demultiplexing unit (24) according to the detected power, so as to form the plurality of laser writing beams (26) by demultiplexing the input laser beam (20).

13. The laser lithography apparatus (10) according to any one of the preceding claims 8 to 12, wherein: The laser lithography device (10) comprises a waveguide arrangement (54) having a plurality of waveguides (56) for guiding the plurality of laser writing beams (26), wherein one waveguide (56) is respectively assigned to one laser writing beam (26). wherein the waveguide (56) is arranged in the beam path between the demultiplexing unit (24) and the objective lens (70), wherein each waveguide (56) has a first end (58) and a second end (60) opposite to the first end (58), wherein each first end (58) is configured to couple a laser writing beam (26), and each second end (60) is configured to decouple the laser writing beam (26) coupled to the first end (58), wherein the second ends (60) of the plurality of waveguides (56) are retained by a retaining matrix (62) of the waveguide arrangement (54).

14. The laser lithography apparatus (10) according to claim 13, wherein: The second ends (60) of the plurality of waveguides (56) are held by the holding matrix (62) in a linear arrangement or a two-dimensional arrangement.

15. The laser lithography apparatus (10) according to any one of the preceding claims 13 or 14, wherein: The distance between two adjacent second ends (60) of the plurality of waveguides (56) is 25 μm to 1000 μm, in particular 115 μm to 600 μm.

16. The laser lithography apparatus (10) according to any one of the preceding claims 13 to 15, wherein: Each second end (60) of the plurality of waveguides (56) has an end face configured to decouple the laser writing beam (26) coupled into the first end (58), Wherein, the end surface of the second end (60) is arranged in a plane.

17. The laser lithography apparatus (10) according to any one of the preceding claims 13 to 16, wherein: The scanning device (78) is configured to move the focal point (72) relative to the photolithographic material receiving portion (14) by moving the holding matrix (62).

18. The laser lithography apparatus (10) according to any one of the preceding claims 13 to 17, wherein: Each waveguide (56) is configured as an optical hollow core fiber.

19. The laser lithography apparatus (10) according to any one of the preceding claims 13 to 18, wherein: Each waveguide (56) is selected from the group consisting of: hollow core photonic crystal fiber, in particular hollow core Kagome fiber, hollow core photonic bandgap fiber, hollow core anti-resonance fiber, hollow core suppressed coupling fiber, radiation-resistant fiber, large mode area fiber, photonic crystal fiber.

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