Method for producing three-dimensional structures in a photoresist by means of a laser lithography device

Abstract

A method for producing a three-dimensional target structure (42) in a lithography material by means of a laser lithography device, wherein the target structure is defined as a focus region (26) of a laser writing beam traversing a scanning manifold (38) through the lithography material within a writing region of the laser lithography device, wherein in the focus region of the laser writing beam an exposure dose is irradiated into the lithography material, and a structure region (52) is locally defined, wherein at least one exposure data set representing the local exposure dose of the scanning manifold as a function of position is determined, wherein a structure approximating the target structure is defined on the basis of the at least one exposure data set, wherein this structure is analyzed and at least one analysis data set representing the analyzed structure is determined, wherein a deviation data set representing a deviation of the defined structure from the target structure is determined, wherein at least one correction exposure data set is determined, and wherein a correction structure is defined on the basis of the at least one correction exposure data set. The invention also relates to a laser lithography device.

Description

Technical Field

[0001] This invention relates to a method for generating a three-dimensional target structure in a photolithographic material using a laser lithography apparatus. The invention also relates to a laser lithography apparatus suitable for this method. Background Technology

[0002] This type of technology is particularly useful for creating microstructures or nanostructures in regions requiring high precision and simultaneously demanding design freedom regarding the desired structure. In such laser lithography methods, the structure is typically written by irradiating the lithographic material in the focused region of the laser writing beam with an exposure dose, thus locally defining the structural region, for example, by locally hardening or polymerizing the lithographic material. The three-dimensional monolithic structure can then be generated by shifting the focused region within the lithographic material.

[0003] A laser lithography method is known from DE 10 2017 110 241 A1, in which a surface with a desired structure is produced by locally changing the exposure dose of radiation (exposure variation).

[0004] To generate high-precision structures using such exposure variations, a relationship must be established between the exposure dose and the exposure result. This typically requires a corresponding calibration process. For this purpose, it is known to generate reference structures with a predetermined exposure dose before actually writing the desired structure, then develop them and subsequently measure their surfaces optically or mechanically. Based on the measurement results, the exposure dose is then typically adjusted accordingly, and this process is repeated until the achieved result meets the specified requirements. However, such optimization processes are usually time-consuming and difficult to automate. Furthermore, this calibration process usually must be repeated at regular intervals. Summary of the Invention

[0005] The purpose of this invention is to generate high-precision three-dimensional structures in photolithography materials in a simple and rapid manner.

[0006] This objective is achieved by a method according to Scheme 1. This method is a laser lithography method using a laser lithography apparatus within the volume of the lithographic material and / or the volume filled with the lithographic material, particularly so-called direct laser writing. According to this method, the target structure is written and / or defined in the lithographic material by sequentially defining multiple structural regions (hereinafter also referred to as "voxels") that are added together to form the target structure (i.e., by "writing" in the lithographic material using a laser lithography apparatus).

[0007] To write the structural region and thus the target structure, the focused area of ​​the laser writing beam passes through a scanning manifold through the lithographic material. In a simple case, the scanning manifold can be a scanning curve, but it can also be made more complex. In other words, the focused area of ​​the laser writing beam is shifted through the lithographic material. For this purpose, the laser writing beam is controllable within the writing area of ​​the laser lithography apparatus, possessing the precision required for structuring purposes. For example, the laser writing beam can be deflected in a controlled manner by a beam guiding device. However, it is also conceivable that the lithographic material or the substrate containing the lithographic material can be shifted in a controlled manner relative to the laser writing beam by a positioning device. The two concepts of shifting can also be used together.

[0008] In the focused region of the laser writing beam, the photolithographic material is irradiated with an exposure dose, particularly utilizing multiphoton absorption, to locally modify the material, thereby creating or writing structural regions. In this respect, the photolithographic material is locally structured, especially utilizing multiphoton absorption. Specifically, the photolithographic material is chemically and / or physically modified, for example, by hardening or polymerization, through the exposure dose of the laser writing beam. The exposure dose is specifically a volumetric dose of radiation energy. The size of the modified structural regions (“voxels”) in the photolithographic material depends on the exposure dose. By changing the exposure dose, the spatial extension of each structural region or voxel, particularly the structural height, can be modified.

[0009] Applying exposure dose via multiphoton absorption may be particularly advantageous in the current types of 3D laser writing. For this purpose, the lithography material is preferably designed in such a way that the laser writing beam is tuned to the lithography material in such a way that changes in the lithography material (e.g., localized polymerization) are possible only through the absorption of a few photons. For this purpose, for example, the wavelength of the laser writing beam can be selected such that—and thus the associated quantum energy—can have an order of magnitude such that the energy input required to modify the lithography material is achieved only by the simultaneous absorption of two or more quanta. The probability of this process is not linearly dependent on intensity and increases significantly in the focused region compared to the rest of the writing beam. Careful consideration shows that the probability of absorbing two or more quanta is a function of the square of the radiation intensity or a higher power. In contrast, the probability of a linear absorption process exhibits a different intensity dependence, particularly at lower power levels of the radiation intensity. Writing deep beneath the liquid surface of the lithography material in the focused region using a linear absorption process would be problematic because the highest absorption probability is not necessarily given even if there is a focal point below the surface of the focused region due to attenuation. On the other hand, the multiphoton absorption mechanism allows for the localized delivery of the required exposure dose even within a certain volume of lithography material, that is, relatively deep below the liquid surface, and can modify the lithography material. Therefore, the device for gradually reducing the support structure in the lithography material bath, as known in the prior art, is unnecessary.

[0010] To address this task, it is particularly recommended to first provide at least one exposure dataset representing the local exposure dose of the scanning manifold as a function of position (step a). Specifically, this at least one exposure dataset may represent the local exposure dose at each scan point along the scan curve of the laser writing beam passing through the lithographic material. In this respect, the at least one exposure dataset specifies the exposure dose to be used at a particular location in the scanning manifold. This at least one exposure dataset is, in particular, stored in the memory of the control device of the laser lithography apparatus. The at least one exposure dataset may be provided, in particular, by providing a structural dataset (e.g., CAD data) representing the target structure to be generated and / or storing it in the control device, and then using it to determine the at least one exposure dataset with computer assistance, for example, through the control device of the laser lithography apparatus configured for this purpose.

[0011] In a further step, a structure approximating the target structure is then defined or generated in the photolithography material based on the at least one exposure dataset (step b). Specifically, the laser lithography apparatus is controlled according to the at least one exposure dataset such that the structural regions are sequentially written into the photolithography material according to the exposure dose specified by the at least one exposure dataset.

[0012] Then, at least a portion of the defined structure is analyzed using an imaging measurement method with spatial resolution (step c). It is conceivable that the structure is analyzed only after the writing process is complete. It is also possible to analyze the structure being analyzed during its definition (i.e., "online"). Specifically, the morphology or shape of the defined structure is measured. In particular, images can be captured using optical measurement equipment, such as OCT (Optical Coherence Tomography). The complete, defined structure can be analyzed. However, it is also possible to analyze only sub-regions of the defined structure—for example, those sub-regions requiring special optimization (e.g., transitional regions resulting from the juxtaposition of substructures created by separated writing regions, see below).

[0013] During or after structural analysis, at least one analysis dataset is determined by a computer, which represents the structure being analyzed, particularly its shape or morphology.

[0014] The computer then determines the deviation dataset, which represents the deviation between the defined structure and the target structure, particularly the deviation in morphology or shape (step d). The deviation dataset is determined specifically by comparing the at least one analysis dataset with a structure dataset representing the target structure to be generated. This structure dataset can specifically be the at least one exposure dataset. Deviation is specifically understood as the difference between the target morphology of the target structure and the actual morphology of the structure defined based on the at least one exposure dataset.

[0015] In a further step (step e), the computer determines at least one corrected exposure dataset, particularly based on a deviation dataset representing the corrected exposure dose required to compensate for the deviation, as a function of position for scanning the manifold.

[0016] Then, a correction structure is generated based on the at least one corrected exposure dataset (step f).

[0017] It is conceivable that, based on a corrected exposure dataset, a separate structure is generated, particularly spatially separate from the structure defined based on the exposure dataset. Then, at least one corrected exposure dataset can specify an exposure dose, specifically for scanning the manifold, as a function of position, where the exposure dose is determined in such a way that the deviation between the structure written based on the corrected exposure dataset and the target structure is smaller than the deviation between a previously written structure based on the exposure dataset and the target structure. The corrected structure can also be used for post-correction of a structure initially written based on at least one exposure dataset. Then, at least one corrected exposure dataset can specify an exposure dose, specifically for scanning the manifold, as a function of position, where the exposure dose is determined such that the deviation between the already defined structure and the target structure is reduced by writing the structure based on the corrected exposure dataset. For example, the corrected structure can be applied to an already written structure.

[0018] This method allows for the characterization of structures already written in situ and direct correction of deviations from the desired target structure. As a result, highly accurate structures can be generated with relatively little time and equipment expenditure. In particular, this method enables the direct detection of deviations from the desired target structure on the generated structure, without the need for prior structure preparation for analysis.

[0019] Specifically, no development of the lithography material occurs between defining the structure (step b) and analyzing the structure (step c). Therefore, in particular, no unexposed lithography material is removed, and the structure already generated based on the exposure dataset is not hardened. Using this method, the written structure can be optimized in situ, resulting in faster cycle times. In particular, this method enables automated structure optimization because complex development steps are no longer required.

[0020] Exposure dose (exposure variation) can be modified by laser modulation, for example by acousto-optic modulators known in the art, or by an automatic polarizer. Other beam-shaping methods can also be used to change the exposure, in which the amplitude, phase, or polarization of the laser-written beam can be adjusted.

[0021] In this context, photolithography material is generally used to refer to a substance whose chemical and / or physical material properties can be altered by irradiation with a writing laser beam, such as so-called photoresist. Based on the type of modification induced by the writing beam, photolithography materials can be classified as so-called negative resists (where irradiation causes localized hardening or a decrease in solubility in the developer medium) and so-called positive resists (where irradiation locally increases solubility in the developer medium).

[0022] According to advantageous developments, steps c) to f) of the above method, namely analyzing the structure and determining at least one analysis dataset (step c), determining the deviation dataset (step d), determining at least one correction exposure dataset (step e), and defining the correction structure (step f), are iteratively repeated such that the deviation between the actually defined structure and the desired target structure gradually decreases, i.e., in each iteration. In other words, after the correction structure has been written, the obtained structure is analyzed again, and further correction structures are written if necessary. Preferably, steps c) to f) are iteratively repeated until the determined deviation is below a predetermined or predeterminable threshold, especially a threshold stored or potentially stored in a control device.

[0023] Imaging measurement methods for analyzing defined structures can be, in particular, optical microscopy, and more especially, nonlinear microscopy. It is conceivable, for example, to first irradiate the structure to be analyzed with excitation light and then detect reflected radiation backscattered, reflected, or transmitted by the structure using an optical measurement device. The measurement device can particularly include measurement optics, which are preferably confocally formed with a device that generates a laser writing beam (e.g., a beam-guiding device). This can also be particularly advantageous if the laser writing beam passes through a lens into the photolithographic material to define the structure, and if the lens is also used to collect radiation emitted by the structure to be analyzed. However, in principle, a separate measurement device, particularly a separate lens, can also be used for microscopy.

[0024] Specifically, the structure was analyzed using confocal fluorescence microscopy. In this regard, the fluorescence signal generated by the photolithography material was evaluated, particularly when excitation light irradiated it. Different fluorescence signals were generated depending on whether the photolithography material was in its unmodified initial state (e.g., unpolymerized) or in a state modified by a laser-written beam (e.g., polymerized), allowing for structural contrast detection.

[0025] In a particularly advantageous embodiment of this method, to analyze a defined structure, it can be optically scanned with a laser writing beam for imaging, and radiation backscattered, reflected, transmitted, or generated by fluorescence can be detected by a measuring device. In this respect, the laser writing beam is used to irradiate the structure being analyzed with excitation light. This scanning using a laser writing beam has the advantage of not requiring additional imaging equipment. Furthermore, analysis can be performed particularly quickly in this manner because, in particular, no optical device switching is required. For scanning the structure, the exposure dose is preferably selected to be sufficiently low such that no structure is defined in the lithography material during scanning. In particular, a laser intensity below the threshold (polymerization threshold) at which significant polymerization occurs in the lithography material is selected. It is also possible to irradiate the structure under examination with lasers of different wavelengths that have such low linear or nonlinear absorption in the lithography material that no structure is defined in the lithography material during scanning.

[0026] Alternatively, the already defined structure can be analyzed using a scanning tip, such as a needle, via mechanical scanning—in the manner of atomic force microscopy. This configuration is particularly advantageous when the photolithography material is initially in a liquid state.

[0027] According to advantageous development, the target structure can be defined by a plurality of sequentially defined substructures, which together at least approximate the target structure. This configuration is particularly advantageous if the target structure to be generated is larger than the maximum write area of ​​the laser lithography apparatus. To generate the substructures, the target structure is preferably rasterized by a computer, particularly decomposed into structural regions (voxels), and each substructure is formed by a set of preferably adjacent structural regions (voxels). To generate the substructures, an additional sub-exposure dataset is then determined by a computer from at least one exposure dataset or at least one correction exposure dataset, which represent the local exposure dose for the scanning manifold for each substructure. In particular, after each substructure has been defined, the write area of ​​the laser lithography apparatus is shifted, for example by positioning devices known in the prior art.

[0028] In principle, the partial structures can have different shapes. It can be particularly advantageous if the target structure to be produced has an extension in the height direction greater than the maximum write height of the laser lithography apparatus, in which case the target structure is at least segmented into partial structures stacked on top of each other in layers. In this respect, at least a subset of the partial structures is designed such that the target structure approximates a plurality of partial structures stacked on top of each other in layers, i.e., one on top of another in the height direction. After writing each partial structure, the lithographic material and / or the substrate having the lithographic material is then moved downwards in a controlled manner, particularly by a positioning device.

[0029] According to an advantageous development, at least one exposure dataset and at least one correction exposure dataset may each comprise at least one grayscale image dataset, wherein different grayscale values ​​represent different exposure doses. Specifically, at least one exposure dataset and at least one correction exposure dataset are each composed of a grayscale image dataset. In this respect, the dataset can be visualized as a grayscale image. Specifically, the laser lithography apparatus is controlled as a function of the grayscale image dataset. Preferably, at least one exposure dataset is provided by reading a grayscale image file into the control device of the laser lithography apparatus and storing it in memory.

[0030] If, as described above, the target structure is composed of partial structures stacked on top of each other in layers, then, if at least one exposure dataset and at least one correction exposure dataset are designed as grayscale image datasets, the grayscale image dataset of at least one exposure dataset and / or the grayscale image dataset of at least one correction exposure dataset are segmented into multiple partial grayscale image datasets. These partial grayscale image datasets together represent an image stack along the stacking direction of the partial structures. The highest grayscale value of each grayscale image then corresponds to the exposure dose that results in the maximum structure height, which can be written on a plane using a laser lithography apparatus (i.e., the lithographic material does not need to move relative to the convergence region of the laser writing beam in the height direction).

[0031] According to a favorable improvement, at least one analysis dataset may also include at least one grayscale image dataset, and in particular, may consist of it, having different grayscale values ​​representing different structural heights of the structure being analyzed. The deviation dataset, in particular the exposure correction dataset, can then be determined by comparing the at least one analysis dataset with at least one exposure dataset.

[0032] The aforementioned objective is also achieved by the laser lithography apparatus according to embodiment 12. The laser lithography apparatus is designed to produce a three-dimensional target structure in a lithographic material. The laser lithography apparatus includes a laser source for emitting a laser writing beam. Furthermore, the laser lithography apparatus includes a beam guiding device, particularly optical devices such as lenses, mirrors, etc., for defining the beam path of the laser writing beam from the laser source to the lithographic material. Additionally, focusing optics are provided, designed to focus the laser writing beam in a focused region. A scanning device is also provided for shifting the focused region of the laser writing beam relative to the lithographic material. The scanning device may be a deflection device (e.g., including a deflector mirror) for modifying the position of the focused region of the laser writing beam in the lithographic material. Additionally or alternatively, the scanning device may also include a positioning device by which the lithographic material or a substrate having the lithographic material can be shifted relative to the laser writing beam.

[0033] The laser lithography apparatus also includes imaging measurement devices for analyzing structures defined or written into the lithographic material by a laser writing beam. Specifically, the measurement devices may include detection equipment for detecting backscattering, reflection, transmission, or generated radiation from fluorescence originating from the structure being analyzed. Additionally or alternatively, the measurement devices may include a probe with a scanning tip through which the structure can be mechanically scanned.

[0034] The laser lithography apparatus also includes a control unit configured to perform the above-described method. The control unit specifically includes a computing unit and a non-volatile memory, in which the above-described dataset is stored or can be stored. Attached Figure Description

[0035] The invention will now be described in more detail using the accompanying drawings.

[0036] In the attached diagram:

[0037] Figure 1 This is a simplified schematic diagram of a laser lithography apparatus;

[0038] Figure 2a , Figure 2b This is a schematic diagram illustrating the sub-steps of a method for generating a three-dimensional structure;

[0039] Figure 3 This is a schematic flowchart of an embodiment of a method for generating three-dimensional structures; and

[0040] Figure 4 and Figure 5 This is a diagram illustrating how the exposure dataset is divided into partial exposure datasets. Detailed Implementation

[0041] In the following description and figures, the same reference numerals are used for the same or corresponding features.

[0042] Figure 1 This is a schematic diagram of a laser lithography apparatus, the entire apparatus of which is indicated by reference numeral 10. The laser lithography apparatus 10 includes a laser source 12 for emitting a laser writing beam 14. The laser lithography apparatus 10 also includes a beam guiding device 16 for defining a beam path 18 of the laser writing beam 14 from the laser source 12 to the lithographic material 20 to be structured, which is shown by way of example as a liquid material bath.

[0043] In the illustrated example, the beam guiding device 16 has multiple modules that implement optical and / or mechanical functions. For example, the beam path 16 may first pass through the modulation module 22 to form a suitable beam pulse. The laser lithography apparatus 10 also includes a focusing region 26 for focusing the laser writing beam 14 onto the laser writing beam 14 (see also...). Figure 2a The focusing optics 24 in the photolithography material 20 includes, for example, a lens module 28 through which the laser writing beam 14 irradiates the photolithography material 20.

[0044] In the illustrated example, the laser lithography apparatus 10 further includes a scanning device 30, by means of which the focusing region 26 of the laser writing beam 14 can be shifted relative to the lithographic material 20 within the writing region 32 with the required structuring precision. In the illustrated example, the scanning device 30 includes a beam guiding module 34, which may include, for example, a galvanometer scanner unit for controlled deflection of the laser beam 14. In embodiments not shown, the scanning device 30 may also include a positioning device for precisely moving the lithographic material 20 or a substrate 36 having the lithographic material 20 relative to the focusing region 26 of the laser writing beam 14. The figures also show a coordinate system with mutually orthogonal axes x, y, z, where the x-axis and y-axis define the writing plane, and the z-axis corresponds to the vertical direction.

[0045] The laser lithography apparatus 10 also includes a control device (not shown), which includes a computing unit and a non-volatile memory.

[0046] To generate a three-dimensional structure in the photolithography material, the focused area 26 of the laser writing beam 14 is shifted relative to the photolithography material 20 by the scanning device 30, such that the focused area 26 passes through the scanning manifold (by the laser writing beam 14) through the photolithography material 20. Figure 1 (Indicated by arrow 38 in the diagram). In the focused region 26 of the laser writing beam 14, the exposure dose is locally irradiated into the photolithographic material 20, making the structural region 40 (see...) Figure 2b () is locally defined, especially by utilizing multiphoton absorption. For example, the photolithography material 20 is locally aggregated and therefore structured.

[0047] The following is for reference. Figures 2a to 5 This explains an advantageous embodiment of a method for generating three-dimensional structures using a laser lithography apparatus, particularly the laser lithography apparatus 10 explained above.

[0048] Figure 2a An example of the target structure is schematically shown in the cross-sectional view, which will be written into the volume of the lithographic material 20 by 3D laser lithography. Target structure 42 in Figure 2a The part is indicated by reference numeral 42 in the accompanying drawings, and has the following characteristics: Figure 2a The outer surface 44 is shown as a dashed line. In the example shown, the target structure 42 has a distinct height profile 46, which is used to explain the effect of exposure dose variations. However, other geometries are of course conceivable. For example, the outer surface 44 of 42 could also have a profile with different gradients or curves.

[0049] For the photolithography of the target structure 42, an exposure dataset is first provided, which represents the local exposure dose of the scanning manifold 38 as a function of position. Figure 3(Step 100 in the process). The exposure dataset can be, in particular, a grayscale image dataset representing the target structure 42. For example, a grayscale image file can be read into the control device of the laser lithography apparatus 10. Alternatively, a structural dataset (e.g., CAD data) representing the target structure 42 can be initially provided, and then the computer determines the exposure dataset based on that structural dataset.

[0050] In the next step ( Figure 3 In step 102), the laser lithography apparatus 10 is then controlled according to the exposure dataset to produce a structure 48 that at least closely approximates the target structure 42 (the outer surface of which is in...). Figure 2b (Drawn in solid lines and indicated by reference numeral 50 in the attached figure). Figure 2a As shown in the example, structure 48 can be defined, for example, through the focusing region 26 across the scanning manifold 38 and during the emission of a sequence of laser pulses with a defined pulse rate and pulse length. This defines a series of structural regions 52 (voxels) forming structure 48 along the scanning manifold 38. Structural regions 52 are similar in shape to each other or identical in shape. The dimensions of the structural regions 52, and therefore the structural height, are related to the absorbed exposure dose.

[0051] Due to various influences (e.g., different local responses of the photolithography material to laser input, optical errors, substrate 36 tilt, etc.), the structure 48 generated based on the exposure dataset typically does not perfectly correspond to the desired target structure 42. According to this method, in a further step ( Figure 3 In step 104), the defined structure 48 is therefore analyzed, particularly the morphology or shape of the defined structure 48 is measured. This occurs in situ, i.e., especially without first developing the lithography material 20 or defining the structure 48. According to the first embodiment, the defined structure 48 is examined using a confocal fluorescence microscope, wherein the defined structure 48 is first optically scanned using a laser writing beam 14, and then the fluorescence signal emitted by the sample is analyzed. For this purpose, the laser lithography apparatus 10 can then have a corresponding measurement device 54 (see...). Figure 1 For example, a fluorescence detector. As an example and preferably, the beam path of the radiation emitted by the sample extends along the beam path of the laser writing beam.

[0052] Structure 48 can also be mechanically scanned for analysis using a scanning tip (not shown). In this case, the laser lithography apparatus 10 may include a scanner (not shown).

[0053] During and / or after the analysis of structure 48, an analysis dataset representing the defined structure 48, particularly its morphology or shape, is then determined. As an example and preferably, the analysis dataset is also a grayscale image dataset, where different grayscale values ​​represent different structure heights (in the z-direction).

[0054] In further steps ( Figure 3 In step 106), the deviation dataset is now determined by comparing the exposure dataset representing the target structure 42 with the analysis dataset representing the deviation between the defined structure 48 and the target structure 42 (see step 106). Figure 2b Specifically, the biased dataset can be determined by the difference between the exposure dataset and the grayscale image dataset of the analysis dataset.

[0055] Then an inspection is performed to determine whether the determined deviation is below a predetermined threshold. Figure 3 (Step 108 in the process). Therefore, it is checked whether the defined structure 48 has sufficiently corresponded to the desired target structure 42. If so, the method ends. Figure 3 Step 110 in the process. However, if the deviation is higher than a threshold, a corrected exposure dataset is determined based on the deviation dataset in a further step. Figure 3 Step 112 in the text represents the corrected exposure dose for each scan point of the scanning manifold 38 to compensate for or at least reduce the deviation from the target structure 42.

[0056] In a further step, the laser lithography apparatus 10 is then controlled based on the corrected exposure dataset. Figure 3 Step 114 in the process defines the correction structure. It is possible to generate a “new” structure spatially separate from the structure defined based on the exposure dataset, particularly at different locations on the substrate 36, based on the correction exposure dataset. The correction structure can also be used solely for post-correction of a structure previously written based on at least one exposure dataset. In this case, the previously traversed scanning manifold 38 can be retraced according to the correction exposure dataset, particularly the focused region 26 of the laser writing beam 14, where the appropriately adjusted exposure dose serves as a function of position.

[0057] Steps 104 to 114 are repeated iteratively until the actual generated structure 48 deviates from the desired target structure 42 by a certain margin below a threshold.

[0058] If the desired target structure 42 is larger than the maximum write area 34 of the laser lithography apparatus 10, the target structure 42 can be computationally decomposed into partial structures that approximate the target structure 42 together. To generate the partial structures, an additional partial exposure dataset is then determined by a computer, specifically based on at least one exposure dataset representing the local exposure dose of the scanning manifold 38 for each partial structure. The partial structures are then written sequentially, and the resulting structures are analyzed and optimized according to the method described above. In this case, the analysis dataset, the bias dataset, and / or the correction exposure dataset may optionally be decomposed into partial datasets based on the partial structures.

[0059] Figure 4An example is depicted where the target structure has a larger extension in the scanning plane (xy plane) than the writing region 34 of the laser lithography apparatus 10. A grayscale image 56 representing the exposure dataset is shown as... Figure 4 Examples are shown in the text. Figure 4 As shown in the example, grayscale image 56 or exposure dataset can be decomposed into partial grayscale images 56a-d and / or partial grayscale image dataset, and then a partial structure is written on top of that.

[0060] When the extension of the target structure 42 in the height direction (z-direction) is greater than the maximum write height of each scanning plane of the laser lithography apparatus 10, the target structure 42 can be decomposed into, for example, partial structures stacked on top of each other in layers. This situation occurs in... Figure 5 The data is depicted in sketch form. To define some of the structure, the dataset (in...) is exposed. Figure 5 The image depicted in grayscale (58) can then be decomposed into multiple partial exposure datasets (in... Figure 5 Described as Figure 5 (From a stack of corresponding grayscale images 58a-h). Grayscale images 58 and 58a-h in Figure 5 The image stack is shown only as a sketch to explain the structure. However, specifically, Figure 5 Each grayscale image 58 or 58a-h in the image corresponds to a color image with the following format: Figure 4 The image shown is a grayscale image in the manner of image 56.

Claims

1. A method for generating a three-dimensional target structure (42) in a photolithographic material (20) using a laser lithography apparatus (10), wherein, The target structure (42) is defined as follows: within the writing region (34) of the laser lithography apparatus (10), the focal region (26) of the laser writing beam (14) passes through the scan curve (38) of the lithography material (20), wherein, within the focal region (26) of the laser writing beam (14), an exposure dose is irradiated into the lithography material (20) and a structural region (52) is locally defined. The method includes: a) Provide at least one exposure dataset, the exposure dataset representing the local exposure dose of the scan curve (38) as a function of position; b) Based on the at least one exposure dataset, define a structure (48) in the lithography material (20) that approximates the target structure (42). c) Analyze the defined structure (48) using spatial resolution imaging measurement methods and determine at least one analysis dataset representing the structure (48) being analyzed; d) Determine the deviation dataset, which represents the deviation between the defined structure (48) and the target structure (42); e) Determine at least one corrected exposure dataset, the corrected exposure dataset representing the corrected exposure dose required as a function of position to compensate for deviations in the scan curve (38); f) Define the correction structure based on the at least one corrected exposure dataset.

2. The method according to claim 1, wherein, No development of the photolithography material (20) occurs between defining the structure (48) according to step b and analyzing the structure (48) according to step c.

3. The method according to claim 1, wherein, Steps c) to f) are repeated iteratively in such a way that the deviation between the defined structure (48) and the target structure (42) gradually decreases.

4. The method according to claim 1, wherein, The defined structure was analyzed using optical microscopy (48).

5. The method according to claim 4, wherein, In order to analyze the defined structure (48), it is scanned with the laser writing beam (14), and for imaging, radiation generated by backscattering, reflection, transmission or fluorescence is detected by the measuring device (54).

6. The method according to claim 1, wherein, In order to analyze the already defined structure (48), it is mechanically scanned using a scanning tip.

7. The method according to claim 1, wherein, The target structure (42) is defined by a plurality of sequentially defined partial structures that together approximate the target structure (42), wherein a computer determines a further partial exposure dataset for defining the partial structures from the at least one exposure dataset and / or the at least one corrected exposure dataset, the further partial exposure dataset representing the local exposure dose along the scan curve of each partial structure.

8. The method according to claim 7, wherein, The partial structures are stacked on top of each other in layers.

9. The method according to claim 1, wherein, The at least one exposure dataset and the at least one corrected exposure dataset each include at least one grayscale image dataset, wherein different grayscale values ​​represent different exposure doses.

10. The method according to claim 8, wherein, To determine the partial exposure dataset, at least one grayscale image dataset of the at least one exposure dataset and / or the at least one corrected exposure dataset is divided into multiple partial grayscale image datasets, which together form an image stack (58a-h) along the stacking direction of the partial structure.

11. The method according to claim 9, wherein, The at least one analysis dataset further includes at least one grayscale image dataset, wherein different grayscale values ​​represent different structure heights, and wherein the deviation dataset is determined by comparing the at least one analysis dataset with the at least one exposure dataset.

12. A laser lithography apparatus (10) for generating a three-dimensional target structure (42) in a photolithography material (20), comprising a laser source (12) for emitting a laser writing beam (14), a beam guiding device (16) for defining a beam path (18) of the laser writing beam (14) from the laser source (12) to the photolithography material (20), a focusing optics (24) for focusing the laser writing beam (14) in a focusing region (26), and a scanning device (30) for shifting the focusing region (26) of the laser writing beam (14) relative to the photolithography material (20), characterized in that An imaging measurement device (54) for analyzing a defined structure (48), and A control device configured to perform the method according to claim 1.

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