Lab-based 3D scanning x-ray laue microdiffraction system and method (Lab3DμXRD)

Abstract

A laboratory-based 3D scanning X-ray scanning Laue microdiffraction system and method for crystal material characterization, comprising: focusing optics, a sample located at a distance from the focusing optics, a laboratory X-ray source, a stage to translate and rotate the sample, a detector arranged to detect a Laue diffraction pattern of diffracted X-rays. The method comprises scanning each layer of the sample by translating the sample at different rotations relative to the focused beam to illuminate each voxel in the layer in more than one rotation, and indexing each voxel in the layer using recorded Laue diffraction patterns in different rotations. By repeating the translation and rotation for different layers of the sample, a 3D image of the sample grain structure is reconstructed.

Description

Technical Field

[0001] This invention relates to the general field of characterization of crystalline materials using diffraction measurements. Background Technology

[0002] Characterizing crystalline materials helps scientists in industry and academia understand their properties and the relationship between processing / manufacturing and properties / performance. This is accomplished by characterizing the crystal orientation of each crystal (also called a grain) in a polycrystalline material using diffraction measurements, where a beam diffracts from individual grains and records the diffraction pattern. To fully characterize a sample, the 3D distribution of the grain orientation needs to be imaged.

[0003] The first form of 3D X-ray diffraction, 3DXRD, was invented 20 years ago. In this method, a monochromatic hard X-ray beam from a high-throughput synchrotron source penetrates the sample to depths of several centimeters in the case of aluminum or several millimeters in the case of steel. In 3DXRD experiments, tomographic data acquisition is performed using layers or box beams that irradiate a segment or portion of the sample volume. High-energy X-ray diffraction microscopy and diffraction contrast tomography (DCT) are branches of 3DXRD, capable of characterizing grains larger than a few micrometers with spatial resolutions as low as approximately 300 nm and standard resolutions of about 1 μm. Currently, characterizing deformable materials and providing information on local intragranular strain using 3DXRD remains challenging.

[0004] Scanning 3DXRD can be used to improve spatial resolution and characterize local strain information, using a focused monochromatic beam where the sample volume is mapped after a series of translation and rotation steps. In all these cases, when using monochromatic X-rays, the resulting diffraction is Bragg diffraction.

[0005] Another form of synchrotron 3D characterization is Laue microdiffraction, in which multicolor X-rays are focused to approximately 0.5 μm in size by a nondispersive Kirkpatrick-Baez mirror and directed onto the sample. A Pt wire or knife-edge is used as a differential aperture to resolve where Laue diffraction occurs along the beam within the sample. 3D volume mapping is achieved after horizontal and vertical translation of the sample. In the case of Laue microdiffraction, sample rotation is not required.

[0006] One limitation of these technologies is their requirement for synchrotron facilities, which are expensive to build and operate, and have limited available beam times. To characterize more materials faster and cheaper, it is crucial that these systems and technologies be adapted to X-rays from laboratory sources. To date, only one such system has been developed: the LabDCT system. The LabDCT system is disclosed in US Patents US8385503B2 and US9383324B2.

[0007] US8385503B2 and US9383324B2, or US 2015 / 0316493 A1, disclose a system in which white / multicolor divergent light from a laboratory X-ray source is guided through a pinhole to a sample. In this system, sample translation is performed to align the sample. The X-ray beam directed at the sample is divergent, thus irradiating a certain volume of the sample. The sample rotates only during LabDCT data acquisition, thus LabDCT operates by using a pinhole that confines the multicolor conical X-ray beam to the desired volume. As the sample rotates, multiple diffraction points from different lattice planes of the same grain can be recorded at a high signal-to-noise ratio on a zone detector. These points are used for indexing crystal orientation and reconstructing the 3D sample volume. However, stress cannot currently be measured.

[0008] Although LabDCT operates using laboratory X-ray sources, it has inherent limitations due to the Laue focusing effect, requiring defect-free crystals / grains. Furthermore, it can only map 3D grains with a spatial resolution of 5–10 μm and is only applicable to grains larger than 20–30 μm. This is insufficient since the typical grain size of most metals is in the 1–25 μm range. Moreover, LabDCT cannot characterize deformable materials or determine local lattice strain within individual grains.

[0009] WO 2009 / 126868 A1 discloses an X-ray generation system that uses focused monochromatic X-rays, or X-rays with a finite discrete energy range rather than a continuous multicolor spectrum, as described in US9383324B2, which are considered too low for DCT. DCT was originally designed based on monochromatic synchrotron X-ray beams.

[0010] Therefore, an improved laboratory-based diffraction system and method would be advantageous, especially one that can characterize small grains on the order of a few μm, determine local lattice strain, and work even when the sample is deformed.

[0011] The project related to this application has been funded by the European Research Council (ERC) under the EU Horizon 2020 research and innovation program (funding agreement number 788567). Summary of the Invention

[0012] Purpose of the invention

[0013] A further object of the present invention is to provide an alternative to the prior art.

[0014] In particular, one object of the present invention can be regarded as providing a laboratory-based 3D scanning X-ray Laue micro-diffraction system that solves the above-mentioned problems in the prior art, characterizes small grains with sizes on the order of a few μm, determines local lattice strain, and is able to characterize deformed samples. Summary of the Invention

[0016] Therefore, a first aspect of the present invention aims to achieve the above-mentioned and several other objectives by providing a laboratory-based 3D scanning X-ray Laue micro-diffraction system for characterizing crystalline materials, the system comprising:

[0017] -Focusing optics

[0018] - A sample located at a certain distance from the focusing optics.

[0019] - A laboratory X-ray source used to generate multicolor X-ray beams.

[0020] The focusing optics are arranged between the X-ray source and the sample in the path of the X-ray beam to generate a focused beam with a spot size diameter of less than 30 μm at image points inside the sample. The focused beam diffracts from the internal sample volume irradiated by the beam, generating diffracted X-rays.

[0021] - A stage for holding the sample, the stage being adapted to rotate and translate the sample relative to the focusing beam at specific intervals and angles.

[0022] - A detector for detecting the Laue diffraction pattern of the diffracted X-rays.

[0023] In some embodiments, the detector is a two-dimensional detector.

[0024] In a second aspect, the present invention also relates to a method for generating 3D orientation imaging of crystalline materials, comprising:

[0025] - A multicolor X-ray beam generated by a laboratory X-ray source is focused onto a spot size smaller than 30 μm within the sample to produce a focused beam.

[0026] - Defines a first translation axis perpendicular to the bundle.

[0027] - Defines a second translation axis perpendicular to the first translation axis and the bundle.

[0028] - Define one or more layers in the predetermined metering volume of the sample along the second translation axis.

[0029] - Scan each layer of the sample using the following steps.

[0030] - Translate the sample along the first translation axis at specific intervals, and record the resulting diffraction pattern for each translation step.

[0031] Each layer of the sample is scanned under different rotations so that each voxel in the layer is illuminated in more than one rotation, such that the Laue diffraction pattern from each voxel is recorded in at least two records.

[0032] The layer is scanned by translating the sample to the next layer along the second translation axis.

[0033] - Index the recorded Laue diffraction pattern to reconstruct a 3D image of the grain structure of the sample.

[0034] The inventors recognized that by combining scanning 3DXRD and Laue microdiffraction techniques, smaller grain sizes and local lattice strain can be characterized in a laboratory system. This invention derives from scanning 3DXRD a data acquisition procedure using stage translation and sample rotation, and from Laue microdiffraction a concept of measuring the Laue diffraction pattern of a multicolor X-ray source and focusing the beam to a smaller spot size. When the sample is scanned by different rotational translations, individual voxels within the sample can be irradiated and detected in multiple records, and the crystal orientation within each voxel can be determined based on these records. By repeatedly scanning and rotating each layer of the sample, a 3D image of the sample can be reconstructed.

[0035] To adapt this technology to laboratory settings that use laboratory X-ray sources, focusing optics may be required to focus the X-ray source to a spot size of less than 30 μm.

[0036] By focusing an X-ray source to a spot diameter of less than 30 μm, grain sizes in the 1–30 μm range can be characterized. Furthermore, the use of multicolor X-rays allows for the application of Laue diffraction techniques, enabling the measurement of local orientation and lattice strain, and the reconstruction of 3D volumes. The lower and upper limits of grain size may depend on the specifications of the focusing optics and the sample under test.

[0037] When using multicolor X-ray beams, local lattice strain within grains of a sample can be measured because this lattice strain can be reconstructed using Laue diffraction patterns. However, since laboratory-based X-ray sources may not be able to produce the flux required for using differential aperture (for synchrotron Laue microdiffraction), it is necessary to combine this technique with scanning 3DXRD to resolve local orientation and strain information within individual grains of a sample.

[0038] To date, no combination of these technologies has been conceived, because it is clear that, due to the complexity of switching from Bragg diffraction to Laue diffraction, even an invention with synchrotron micro-diffraction has not been conceived.

[0039] This method can use both traditional and non-traditional indexing methods to index Laue diffraction patterns. The latter can use machine training methods or deep learning.

[0040] Therefore, this invention combines the techniques of two synchrotron methods in a novel and inventive manner to create a laboratory-based 3D scanning Laue micro-diffraction system and method (Lab3DμXRD).

[0041] In US9383324B2, sample translation is used only for alignment before data acquisition, not for data acquisition. The focusing system in WO2009 / 126868A1 produces only monochromatic X-rays, or X-rays with a limited range of discretized energies but not continuous multicolor spectra, as described in US9383324B2, which is considered too low for DCT. DCT was originally designed based on monochromatic synchrotron X-ray beams.

[0042] The focusing system described in WO 2009 / 126868 A1 is mainly used for focusing monochromatic beams and typical soft X-rays (energy below 10 keV), while the system according to the invention realizes focusing optics that produce hard multicolor X-rays (energy > 10 keV) with continuous energy spectrum focusing, which is particularly challenging, especially with a small spot size of <20-30 μm.

[0043] In a preferred embodiment, the system may include a shield that can be positioned between the source and the sample, and a beam blocker that can be positioned after the sample. If the detector is placed in the path of the transmitted beam, having a beam blocker after the sample to block the transmitted beam may be advantageous, thereby protecting the detector. Having a shield is advantageous because it blocks direct beams from the source that have not passed through the focusing optics, thereby improving the contrast of the diffraction pattern.

[0044] In a preferred embodiment, the laboratory X-ray source can generate multicolor beams with X-ray energy ranging from 5 to 150 keV.

[0045] In a preferred embodiment, the focusing optics can focus the X-ray beam to a spot size diameter of less than 20 μm, preferably less than 10 μm, more preferably less than 5 μm, or most preferably less than 1 μm.

[0046] Having a spot size diameter that is as small as the smallest grain to be measured in the crystalline material may be advantageous.

[0047] In a preferred embodiment, the detector may be a photon counting, flat panel, scintillator-based CCD, or CMOS detector type.

[0048] In a preferred embodiment, the focusing optics may be a double parabolic X-ray mirror optics, an elliptical multi-capillary optics, a Kirkpatrick-Baez mirror, etc.

[0049] By using different focusing optics, the spot diameter of the focused beam can be selected according to the specifications and requirements of the sample and 3D characterization.

[0050] In a preferred embodiment, two or more detectors may be arranged at different positions in the diffraction X-ray path, and the detectors may have non-overlapping regions in the radial plane defined by the diffraction X-rays.

[0051] In a preferred embodiment, the detector can be placed 5-10 mm to one meter away from the sample, and the focusing optics can be placed 20-50 mm away from the sample (measurement can be performed from the end of the optics to the sample).

[0052] In a preferred embodiment, the translation step size along the first translation axis can be selected based on the beam size and the grain size of the sample. The translation interval may be in the range of beam spot size, 1-30 μm or larger.

[0053] In a preferred embodiment, the translation range may cover part or all of the longest side of the sample under different rotations. In other embodiments, the rotation and translation intervals and step sizes may be selected based on the metrological volume to be characterized within the sample. In a preferred embodiment, the translation intervals and ranges along the first translation axis may be the same for different rotations of the sample. However, in other embodiments, different translation ranges and intervals may be used for different rotations.

[0054] In this case, the defined voxels may not be uniformly distributed. This can be advantageous in certain situations, such as when there are pores in the sample, allowing the translation to skip over these pores. In another embodiment, the translation step size can be the same at one rotation angle but different at different rotation angles. For example, a translation step size of 0 degrees could be 1 unit, a translation step size of 45 degrees could be sqrt(2) / 2 units, etc. Alternatively, the translation step size can be pre-characterized at each rotation, thus skipping translation steps where the beam is not guided into the sample.

[0055] In a preferred embodiment, spatial resolution can be improved by translating the sample with a step size smaller than the spot diameter of the focused beam.

[0056] In a preferred embodiment, the rotations can add up to a quarter turn, half a turn, or a full turn, but other rotation ranges are conceivable. In a preferred embodiment, the rotation interval can be on the order of 1 to 90 degrees and is the same for different rotations. In such an embodiment, the sample can be rotated multiple times, for example, seven times at intervals of 0 degrees, 30 degrees, 60 degrees, 90 degrees, 120 degrees, 150 degrees, and 180 degrees, such that each layer is scanned seven times. In some embodiments, the rotation interval can be varied for each rotation, for example, the first rotation is 30 degrees, then 60 degrees, and so on.

[0057] However, depending on the sample to be characterized, translation and rotation can be any combination of range and interval. This ensures that individual voxels within the sample can be recorded by more than one record. It can be used to select measurements to record selected voxels in individual measurements.

[0058] In a preferred embodiment, Laue diffraction patterns are detected at different time intervals to create a 4D image, where time is the fourth dimension, as the crystalline material may be exposed to any external stimuli.

[0059] In a preferred embodiment, the index belongs to the following types: pattern matching, dictionary index, deep learning.

[0060] Preferred volumetric measurement refers to the volume within the sample to be characterized.

[0061] The internal sample volume preferably refers to the volume inside the sample irradiated by the beam during the measurement.

[0062] Voxel optimization refers to a defined volume within a sample. The shape of a voxel may differ from that of a cubic element. Voxels may overlap.

[0063] Scanning optimization refers to performing new measurements along the scanning direction relative to the beam translation of the sample.

[0064] Range preference refers to the distance / rotation angle between the first and last translation / rotation. Step size preference means the change in distance / rotation.

[0065] Layer selection refers to virtual slices of a sample.

[0066] The preferred beam spot size diameter refers to the cross-sectional diameter of the smallest dimension in the beam.

[0067] Laboratory X-ray sources preferably refer to machines and sources used in a laboratory environment and are negatively defined as not synchrotron beams.

[0068] Indexing optimization refers to identifying diffraction spots in a diffraction image and determining which lattice planes of the grain (or voxel) they diffract from, thereby determining the crystal orientation of the grain (or voxel).

[0069] Recording optimization refers to detecting and storing the diffraction pattern from the detector for a single measurement.

[0070] Measurement optimization refers to beam exposure of the sample at a specific time during the recording of the diffraction pattern. Attached Figure Description

[0071] The diffraction system and method according to the invention will now be described in more detail with reference to the accompanying drawings. The drawings illustrate one mode of carrying out the invention and should not be construed as limiting other possible embodiments falling within the scope of the appended claims.

[0072] Figure 1A This describes one embodiment of the device of the present invention.

[0073] Figure 1B This illustrates an embodiment of an internal sample volume irradiated by a focused beam.

[0074] Figure 1C This describes an embodiment of the method according to the present invention.

[0075] Figure 2 One embodiment of the invention is illustrated, in which the detector is positioned at a 90-degree angle relative to the incident beam.

[0076] Figure 3 An embodiment is illustrated, in which three detectors are used to detect the diffraction pattern.

[0077] Figure 4 This is a flowchart of an embodiment of the method according to the present invention, and

[0078] Figure 5 An example of a voxel is shown. Detailed Implementation

[0079] Figure 1A An embodiment of a laboratory-based 3D scanning X-ray Laue micro-diffraction system 1 for characterizing crystalline materials is shown. The system includes: a sample 7 to be characterized, located at a distance from a focusing optics 4; a laboratory X-ray source 2 for generating a multicolor X-ray beam 3 guided into the focusing optics 4, such that the focusing optics 4 is positioned between the X-ray source 2 and the sample 7 in the path of the beam 3, producing a focused beam with a spot size diameter less than 30 μm at an imaging point located inside the sample. The sample 7 is preferably a crystalline material.

[0080] The focusing beam 5 irradiates the internal sample volume 12 within the sample 7, thereby generating diffracted X-rays 8 from the entire irradiated internal sample volume 12. The internal sample volume 12 can... Figure 1B Seen in ). In Figure 1BIn this embodiment, due to the focal length, the focused beam 5 is cylindrical within the sample 7. In some embodiments, the focal length will be greater than or equal to the thickness of the sample 7, but the shape of the irradiated internal sample volume 12 depends on the focused beam 5, i.e., the relative position of the irradiated sample 7 and the focal point within the sample, and the size of the focal length. In some embodiments, the sample thickness may be greater than the focal length, so that the beam will diverge or converge within the sample, making the internal sample volume 12 not cylindrical.

[0081] The diffracted X-rays 8 are detected and recorded by detector 9, which is positioned in the path of the diffracted X-rays 8 to detect the Laue diffraction pattern 13 of the internal sample volume 12. In one embodiment, the detector may be placed in a transmission or reflection geometry.

[0082] In one embodiment, detector 9 may be of the following types: photon counting, flat panel, scintillator-based CDD or CMOS detector, etc.

[0083] The system also includes a stage 6 adapted to support, rotate, and translate a sample 7 relative to the focusing beam 5. In one embodiment, the translation of the sample 7 by the stage 6 can occur in two directions perpendicular to each other. In some embodiments, the stage 6 may consist of multiple components, such as a support for fixing the sample and a goniometer device for translating and rotating the support.

[0084] Stage 6 is adapted to rotate and translate sample 7 at specific intervals and angles, allowing sample 7 to be scanned in a grid-like manner under different rotations, such as... Figure 1C As shown in the figure.

[0085] In one embodiment, sample 7 can be translated along a first translation axis perpendicular to the bundle and a second translation axis perpendicular to both the first and bundle axes. The desired metrological volume of sample 7 is layered along the second translation axis.

[0086] Therefore, the method involves scanning sample 7 layer by layer along a first translation axis perpendicular to the beam. Figure 1C In (i), a top view of sample 7 along the second translation axis is shown, wherein sample 7 is scanned by translating the sample in 5 steps along the y-axis. Figure 1C In the diagram, the y-axis corresponds to the first translation axis, the z-axis corresponds to the second translation axis, and the beam propagates along the x-axis.

[0087] Each of these translation steps corresponds to the individual measurement and recording of the Laue diffraction pattern 13 produced by the different internal sample volumes 12 being irradiated. Figure 1C In i), most X-ray beams appear as lines, but as... Figure 1C In i), for a beam, the beam will have a finite size, so that the internal sample volume within the sample is irradiated.

[0088] After scanning sample 7 along the y-axis, sample 7 is rotated at specific rotation intervals and scanned along the y-axis again, such as... Figure 1C As shown in ii), sample 7 is rotated 90 degrees and scanned along the y-axis again after each rotation.

[0089] The rotation and translation step size depends on the sample. Each translation in the scanning step is measured individually, therefore... Figure 1C In the example shown in iii), 5*2=10 measurements were performed on one layer of sample 7.

[0090] In some embodiments, the data collection process is as follows: guiding the beam to the beginning of a translation range within a layer of sample 7, recording the Laue diffraction pattern 13, translating sample 7 along the translation range in translation steps, and recording a new Laue diffraction pattern 13. When the translation covers the entire translation range, sample 7 is rotated and the translation steps are repeated. In this embodiment, the rotation axis is the z-axis, but in some embodiments, the rotation axis may be independent of the first and second translation axes.

[0091] Once the full rotation or the desired rotation range has been achieved, sample 7 translates along the second translation axis. Figure 1C This is the z-axis, used to scan the next layer. In some embodiments, the axes do not need to be perpendicular to each other.

[0092] By scanning sample 7 with different rotations, each voxel 15 of sample 7 can be illuminated during at least two measurements. Voxel 15 is a defined volume within sample 7, such as... Figure 1C ) of iii) and iv) and Figure 5 As shown.

[0093] Voxels 15 can be reconstructed by indexing Laue diffraction patterns 13 using two or more records with diffraction patterns 13 from the same voxel 15. Each voxel 15 in the sample can be indexed individually, and the 3D image of sample 7 is reconstructed sequentially. By having smaller translation and rotation steps, each voxel 15 will be illuminated in more measurements, and the resolution will be improved.

[0094] It is clear that the selection of the rotation and translation range and step size is to ensure that each voxel 15 is recorded in at least two records, but the size of the voxel 15 can also be selected based on a fixed translation and rotation step size and / or bundle size. In some embodiments, voxels 15 may have different sizes within the sample, which will occur if the translation or rotation step size is non-linear and may overlap. In some embodiments, the translation and rotation step size is selected to characterize only certain voxels within the metrological volume.

[0095] This means that, in order to extract information about the crystal orientation of each defined voxel, signals from shared internal volumes measured at different times are indexed. These shared volumes (i.e., voxels) can be determined based on translation and rotation priors, for example... Figure 1C Voxel 15 in (iii) is defined by translation measurement 3 with 0-degree rotation and measurement 3 with 90-degree rotation.

[0096] Voxel 14 is reconstructed using a second measurement with 0-degree rotation (starting from the top) and a third measurement with 90-degree rotation. Therefore, the measurement record used to reconstruct a specific voxel can be selected a priori in the same manner before the measurement. If only voxels 14 and 15 are to be characterized, only three measurements are needed. Therefore, the measurement procedure can be selected a priori based on the required metrological volume and the voxels within that volume.

[0097] Therefore, the translation step size and range, as well as the rotation, are selected based on the voxels in the metrological volume, ensuring that each voxel is fully or partially irradiated during at least two measurements. The measurements may contain metadata about the translation and rotation step sizes to select the correct measurements for voxel reconstruction. Figure 1C In this measurement, the measurements may include metadata about the scan position, rotation position, and layer position. This data may also include (first translation axis coordinates, second translation axis coordinates, rotation) data for sample 7, which may be provided by the stage, for example, by the positioning components within stage 6.

[0098] This method can be viewed as projecting a grid onto the surface of sample 7. The sample is then rotated while keeping the grid points spatially fixed, so that the same grid points are projected onto the newly rotated sample 7 with the same spatial coordinates. The specific rotation and translation step size and layer size are selected based on the shape and thickness of the sample and beam, as well as other measurement factors.

[0099] For example, with a rotation step of 90 degrees, a rotation range of 360 degrees, 5 translations along the y-axis, and 3 layers scanned, such as... Figure 1C As shown in the figure, the number of measurements was 4*5*3=60, of which at least 5*5*3=75 individual voxels in sample 7 could be characterized. Some measurements may be empty measurements.

[0100] The internal sample volumes 12 illuminated by the focused beam 5 may overlap in some embodiments and not in others. The number and overlap of these internal sample volumes can determine the resolution of the generated 3D image.

[0101] With such a system, in one embodiment, the characterization of grains with sizes > 1 μm can be achieved. The specific grain size that can be characterized may depend on the selected overlap between the specifications of the focusing optics 4 and the internal sample volume 12. The focusing optics 4 focuses the X-ray beam to the desired size and increases the flux. Thus, this system combines the concept of synchrotron scanning 3DXRD with synchrotron Laue microdiffraction in a laboratory setting.

[0102] In a preferred embodiment, the laboratory X-ray source 2 generates a multicolor beam 3 with X-ray energies in the range of 5-150 keV. These energies can typically be generated by an X-ray tube using a metal target, a rotating anode, a liquid metal anode, or a linear accelerating source. In some embodiments, the source 2 can also be a synchrotron source with correspondingly higher throughput. The disclosed systems and methods are equally applicable to laboratory settings and synchrotron settings.

[0103] In one embodiment, the focusing optics 4 focuses the X-ray beam to a spot size diameter of less than 20 μm, preferably 10 μm, more preferably 5 μm, and most preferably 1 μm. This beam focusing simultaneously enhances the intensity of the focused beam 5.

[0104] The choice of optical device 4 will depend on the grain to be characterized. For example, when characterizing 1-5 μm grains, it is best to choose focusing optical device 4 to focus beam 3 to a spot size diameter of less than 5 μm. In one embodiment, focusing optical device 4 can focus beam 3 to a spot size diameter of less than 1 μm, so that 1 μm grains can be studied in the best manner.

[0105] In some embodiments, the focusing optics 4 are a double parabolic X-ray mirror, an ellipsoidal optics, a multi-capillary optics, and a Kirkpatrick-Baez mirror, etc. By using a double parabolic X-ray mirror, the beam 4 can be focused to a spot size diameter of 5 μm or even smaller.

[0106] The detector 9 can be positioned at an angle to the incident beam, as long as the diffracted beam originating from the internal sample volume 12 can be measured. In such an embodiment, a beam blocker 10 is not required because the detector is not placed in the path of the transmitted beam 11. If the detector 9 were placed in the path of the transmitted beam 11, a beam blocker 10 could be placed to block the transmitted beam.

[0107] like Figure 2 As shown, in one embodiment, detector 9 can be positioned at a 90-degree angle relative to the focused beam 5. Therefore, the detector can be positioned in a transmission geometry (0 degrees), a reflection mode (90 degrees), a rear projection mode (180 degrees), or any other angle. The system may include a shield 16 between source 2 and sample 7 to block the direct beam from source 2.

[0108] like Figure 3 As shown, in one embodiment, two or more detectors 9 can be arranged at different positions in the path of the diffraction X-ray 8, and the detectors 9 have non-overlapping regions in the radial plane defined by the diffraction X-ray 8. Therefore, a large detector region can be created by placing several smaller detectors 9 side-by-side.

[0109] In one embodiment, detector 9 can be placed 5-10 mm to one meter away from sample 7 and focusing optics 4 can be placed 20-50 mm away from sample 7 (measured from the end of focusing optics). The precise placement of detector 9 and optics 4 depends on the required spot size diameter, optics working distance, detector pixel size, and other external factors.

[0110] Figure 4 A flowchart of a method for generating a 3D image of a sample is shown. The method first involves focusing a laboratory X-ray source 2 to a spot size diameter of less than 30 μm, guiding the focused beam 5 into the sample 7 to be characterized, thereby irradiating the internal sample volume 12 to generate diffracted X-rays 8. In this example, beams 3 and 5 are horizontal, thus the first translation axis is horizontal and the second translation axis is vertical.

[0111] In the second step of the method, sample 7 is horizontally scanned relative to beams 3 and 5. Each translation corresponds to a new measurement, during which the Laue diffraction pattern is recorded. When sample 7 has been fully horizontally scanned, sample 7 is rotated in the third step and horizontally scanned again according to step 2.

[0112] Once sample 7 has been fully rotated according to the rotation specification, in step four, sample 7 is vertically translated to characterize a new layer of sample 7, and steps 2 through 4 are repeated. This continues until all metrological volumes of sample 7 selected for characterization have been scanned.

[0113] Once sample 7 has been fully scanned, the record of diffraction pattern 13 can be used to index the individual voxels 15 of the metrological volume to reconstruct a 3D image of the sample. Clearly, steps 2, 3, and 4 are interchangeable, can be performed in any order, and rotation can be performed in any step or in combination.

[0114] The thickness and translation dimensions of the layer can be preselected based on voxel 15 to be characterized in the metrological volume of sample 7.

[0115] In one embodiment, the internal sample volume 12 covers the volume of sample 7 that can be irradiated by the focused beam 5 by rotating and translating sample 7 at specific intervals. The scanned sample volume, also known as the metrological volume, can reconstruct all voxels within the metrological volume.

[0116] If only a portion of the sample is being characterized, then when the sample is rotated, only that portion is covered by the scanning range. Therefore, the metrological volume could be a part of the sample or the entire sample.

[0117] In some embodiments, there is an overlapping region between the internal sample volumes 12 during the scanning of sample 7, such that sample 7 is translated during scanning in steps smaller than the diameter of the spot of the focused beam 5. The exact location and number of internal sample volumes 12 depend on the specific requirements of sample 7, such as the required resolution, coverage, sample size, etc.

[0118] In one embodiment, the rotation interval can be on the order of 1 to 90 degrees, and the translation interval can be the size of the beam spot, for example, between 1 and 30 μm, and the thickness of the layer can also be within the range of the beam spot size, for example, between 1 and 30 μm, to ensure that the entire metrology volume is irradiated and all internal sample volumes 12 become metrology volumes.

[0119] Once a sufficient internal sample volume 12 has been irradiated with a focused beam, such that the diffraction pattern 13 from each voxel to be characterized has been recorded by at least two measurements, the recorded diffraction pattern 13 is indexed to reconstruct a 3D image of the grain structure of sample 7. This is accomplished by individually indexing the pattern for each voxel and reconstructing the 3D volume by interpolating voxels with different indices.

[0120] In one embodiment, the index can be pattern matching, dictionary indexing, or performed by using deep learning methods or other types of trained networks (e.g., AI, neural networks, etc.).

[0121] When sample 7 is exposed to external stimuli, its structure and properties may change over time. Therefore, a 4D image of the sample can be constructed by detecting Laue diffraction patterns at different time intervals over the same internal sample volume. This allows for the monitoring and examination of crystalline materials under external stimuli.

[0122] In summary, the present invention may include one or more of the following:

[0123] i. A laboratory-based 3D scanning X-ray Laue micro-diffraction system for characterizing crystalline materials (1), comprising:

[0124] -Focusing optics (4),

[0125] -The sample (7) located at a certain distance from the focusing optics (4),

[0126] - A laboratory X-ray source (2) for generating multicolor X-ray beams (3),

[0127] - The focusing optics (4) are arranged in the path of the X-ray beam (3) between the X-ray source (2) and the sample (7) to generate a focused beam (5) with a spot size diameter of less than 30 μm at the image point inside the sample (7). The focused beam (5) diffracts from the internal sample volume (12) irradiated by the beam (5) inside the sample (7) to generate diffracted X-rays (8).

[0128] - A stage (6) for holding the sample (7), the stage (6) being adapted to rotate and translate the sample (7) relative to the focusing beam (5) at specific intervals and angles.

[0129] - Detector (9) for detecting the Laue diffraction pattern (13) of the diffracted X-rays (8).

[0130] ii. A method for generating 3D orientation imaging of crystalline materials, comprising:

[0131] - A multicolor X-ray beam (3) generated by a laboratory X-ray source (2) is focused onto a spot with a diameter less than 30 μm within the sample (7) to generate a focused beam (5).

[0132] - Defines a first translation axis perpendicular to the bundle (5),

[0133] - Define a second translation axis perpendicular to the first translation axis and the bundle (5),

[0134] -One or more layers are defined in the predetermined metering volume of the sample (7) along the second translation axis.

[0135] - Scan each layer of the sample (7) using the following steps.

[0136] - Translate the sample (7) along the first translation axis at specific intervals, and record the diffraction pattern obtained at each translation step.

[0137] Each layer of the sample (7) is scanned under different rotations of the sample (7) so that each voxel (15) in the layer is irradiated in more than one rotation, such that the Laue diffraction pattern from each voxel (15) is recorded in at least two records.

[0138] The layer is scanned by translating the sample (7) to the next layer along the second translation axis.

[0139] - Index the recorded Laue diffraction pattern (13) to reconstruct a 3D image of the grain structure of the sample (7).

[0140] Although the invention has been described in conjunction with specific embodiments, it should not be construed as limiting the examples presented in any way. The scope of the invention is set forth by the appended claims. In the context of the claims, the terms "comprising" or "including" do not exclude other possible elements or steps. Furthermore, references such as "a" or "an" should not be construed as excluding a plurality. The reference numerals used in the claims, in relation to the elements indicated in the drawings, should also not be construed as limiting the scope of the invention. Moreover, the various features mentioned in different claims may be advantageously combined, and the mention of these features in different claims does not preclude the possibility and advantage of combining features.

[0141] Figure Labels

[0142] 1. Laboratory-based 3D scanning X-ray Laue micro-diffraction system

[0143] 2. Laboratory X-ray source

[0144] 3. Multicolor X-ray beam

[0145] 4. Focusing optics

[0146] 5. Focusing Beam

[0147] 6. Taiwan

[0148] 7. Sample

[0149] 8. Diffraction X-rays

[0150] 9. Detector

[0151] 10. Beam stopper

[0152] 11. Transmitted beam

[0153] 12. Internal sample volume

[0154] 13. Laue diffraction pattern

[0155] 14. Another voxel

[0156] 15. Voxels

[0157] 16. Shielding device

Claims

1. A method for generating 3D orientation imaging of crystalline materials, comprising: - A multicolor X-ray beam (3) generated by a laboratory X-ray source (2) is focused onto the sample (7) to produce a focused beam (5) with a spot size diameter of less than 30 μm. - Defines a first translation axis perpendicular to the focusing beam (5), - Define a second translation axis that is perpendicular to the first translation axis and the focusing beam (5). -One or more layers are defined in the predetermined metering volume of the sample (7) along the second translation axis. - Scan each layer of the sample (7) using the following steps. - Translate the sample (7) along the first translation axis at specific intervals, and record the resulting diffraction pattern for each translation step. Each layer of the sample (7) is scanned under different rotations of the sample (7) so that each voxel (15) in the layer is irradiated in more than one rotation, such that the Laue diffraction pattern from each voxel (15) is recorded in at least two records. The layer is scanned by translating the sample (7) to the next layer along the second translation axis. - Index the recorded Laue diffraction pattern (13) to reconstruct a 3D image of the grain structure of the sample (7).

2. The method of claim 1, wherein the translation step size along the first translation axis is selected based on the size of the focusing beam and the sample (7), and the translation range covers a portion or all of the longest side of the sample during rotation.

3. The method according to claim 1, wherein the rotation interval is on the order of 1 to 90 degrees, and the translation interval has a range of 1-30 μm corresponding to the spot size.

4. The method of claim 1, wherein the interval of rotation is the same for different rotations, or varies for each rotation.

5. The method of claim 4, wherein the rotational change comprises a first rotation of 30 degrees, followed by a rotation of 60 degrees.

6. The method of claim 1, wherein the rotations add up to a predetermined rotation range, the predetermined rotation range including any one of a quarter turn, half turn, or full turn of the sample.

7. The method of claim 1, wherein the Laue diffraction pattern is detected at different time intervals to generate a 4D image of the crystalline material, wherein time is the fourth dimension.

8. The method according to claim 1, wherein the index is of the following types: pattern matching, dictionary index, deep learning.

9. A laboratory-based 3D scanning X-ray Laue micro-diffraction system (1) for characterizing crystalline materials by performing the method according to claim 1, comprising: -Focusing optics (4), - The sample (7) located at a certain distance from the focusing optics (4), - A laboratory X-ray source (2) for generating multicolor X-ray beams (3), The focusing optics (4) are arranged in the path of the X-ray beam (3) between the X-ray source (2) and the sample (7) to generate a focused beam (5) with a spot size diameter of less than 30 μm at the image point inside the sample (7). The focused beam (5) diffracts from the internal sample volume (12) irradiated by the focused beam (5) inside the sample (7) to generate diffracted X-rays (8). - A stage (6) for holding the sample (7), the stage (6) being adapted to rotate and translate the sample (7) relative to the focusing beam (5) at specific intervals and angles. - Detector (9) is arranged to detect the Laue diffraction pattern (13) of the diffracted X-rays (8).

10. The system according to claim 9, wherein a beam blocker (10) for blocking the transmission beam (11) is arranged after the sample (7), and / or a shield (16) is arranged between the sample (7) and the X-ray source (2), the shield (16) for blocking the X-ray beam (3) from the X-ray source (2) that has not passed through the focusing optics (4).

11. The system according to claim 9, wherein, The laboratory X-ray source produces multicolor X-ray beams with an energy range of 5-150 keV.

12. The system of claim 9, wherein the focusing optics (4) focuses the X-ray beam to a spot size diameter of less than 20 μm.

13. The system of claim 12, wherein the focusing optics (4) focuses the X-ray beam to a spot size diameter of less than 10 μm.

14. The system of claim 13, wherein the focusing optics (4) focuses the X-ray beam to a spot size diameter of less than 5 μm.

15. The system of claim 14, wherein the focusing optics (4) focuses the X-ray beam to a spot size diameter of less than 1 μm.

16. The system according to claim 9, wherein, The detector (9) is a photon counting, flat panel, scintillator-based CCD or CMOS detector type.

17. The system according to claim 9, wherein the focusing optics (4) comprises at least one of a double parabolic X-ray mirror optics, an elliptical multi-capillary optics, and a Kirkpatrick-Baez mirror.

18. The system of claim 9, wherein two or more detectors (9) are arranged at different positions in the path of the diffracted X-ray (8), the detectors (9) having non-overlapping regions in a radial plane defined by the diffracted X-ray (8).

19. The system according to claim 9, wherein, The detector (9) is placed 5-10 mm to 1 meter away from the sample (7), and the focusing optics (4) is placed 20-50 mm away from the sample (7), with measurements taken from the end of the focusing optics (4).

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