Sample mounting system for X-ray analysis equipment

Abstract

To provide a sample mounting system for an X-ray analysis apparatus.SOLUTION: The sample mounting system comprises a sample holder, and a sample stage having a platform for supporting the sample holder. The sample can be fixed to the sample holder by a mount. The sample holder comprises a holder reference portion, which co-operates with a corresponding reference portion of the sample stage (a stage reference portion) to align the sample holder with the sample stage. When the sample holder is positioned on the platform such that the stage reference portion and the holder reference portion engage each other, the sample holder is aligned with the sample stage.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to the field of analyzing material samples by X-ray analysis, such as by X-ray diffraction analysis, X-ray fluorescence analysis, X-ray computed tomography, or X-ray scattering analysis. More particularly, the present invention relates to a sample mount system for use in an X-ray analysis apparatus, an X-ray analysis apparatus including the sample mount system, and a method of using the sample mount system. [Background technology]

[0002] In the field of materials science, X-ray analysis can be used to characterize material samples. X-ray analysis instruments typically include an X-ray source, a sample stage, and an X-ray detector. The X-ray source is positioned to irradiate the sample, and the X-ray detector is positioned to detect X-rays emitted or scattered by the sample. During this analysis, the sample is held or contained in a sample holder located in the X-ray analysis instrument.

[0003] Samples are analyzed by measuring the magnitude and / or position of X-ray intensity peaks measured by an X-ray detector. Proper alignment of the X-ray analyzer is important for reliable results. For example, when analyzing a sample by X-ray diffraction analysis performed in reflection geometry, the diffraction peak position is sensitive to the height of the sample surface. If the sample is displaced from the center of the goniometer, the diffracted X-rays will be received by the X-ray detector at a position corresponding to a different 2θ angle. Therefore, the diffraction peaks will appear to shift, potentially resulting in errors in the characterization of the sample.

[0004] In some cases, it is desirable to perform X-ray analysis by comparing the results of a sample to results obtained using one or more reference standards. Similarly, in this type of analysis, it is desirable to ensure that the sample is positioned in a repeatable manner.

[0005] It would be desirable to reduce / avoid possible errors associated with sample misplacement. It would also be desirable to facilitate minimal operator input. Summary of the Invention

[0006] In one aspect of the present invention, there is provided a sample mount system for an X-ray analysis instrument, the sample mount system comprising: a sample holder including a mount, the mount securing a sample to an upper surface of the sample holder, the sample holder further including a holder reference portion; a sample stage including a platform for supporting a sample holder, the sample stage including a stage reference portion for cooperating with the holder reference portion to position the sample holder on the platform; Including, The sample holder and sample stage have an alignment configuration in which the sample holder is placed on the platform so that the stage reference portion and the holder reference portion engage each other.

[0007] The sample stage and sample holder are aligned when the sample holder is placed on the platform such that the stage datum portion and the holder datum portion engage. Repeatable positioning of the sample holder on the sample stage is facilitated by providing an arrangement in which the sample holder and sample stage engage when they are in an aligned configuration.

[0008] If the sample holder and sample stage are not aligned, the holder reference portion and the stage reference portion cannot engage with each other, thereby helping to prevent incorrectly aligned measurements and analyses from being performed.

[0009] When the stage reference portion engages / couples with the holder reference portion, the orientation of the sample holder can be fixed, or the sample holder can freely change its orientation.

[0010] The stage and holder reference portions can assist the user in determining the correct position (orientation and / or orientation) for the sample holder on the platform.

[0011] The one or more holder reference portions may be provided on any surface of the sample holder, such as, for example, the top surface (i.e., the surface on which the sample is mounted), and / or the bottom surface (the surface opposite the top surface), and / or at least one side surface of the sample holder. Similarly, the one or more stage reference portions may be provided in any location suitable for engaging with the holder reference portion to align the sample holder. For example, if the holder reference portion is provided on the bottom surface of the sample holder, the stage reference portion may be located below the sample holder (on the same side of the sample holder as the bottom surface) rather than above the sample holder.

[0012] The sample holder may have a central axis, and the stage reference portion and holder reference portion may be configured such that, in the aligned configuration, engagement of the stage reference portion and holder reference portion holds the sample holder and limits and / or prevents rotation of the sample holder about its central axis. In some embodiments, when the stage reference portion engages / couples with the holder reference portion, the sample holder may rotate about its central axis such that the orientation of the sample holder is adjustable. In some other embodiments, the orientation of the sample holder relative to the platform may be limited or fixed. For example, engagement of the stage reference portion and holder reference portion may limit or prevent rotation of the sample holder about its central axis.

[0013] The mount may be configured to secure a sample vessel for containing the sample to the sample holder. The mount may be a mechanism for attaching a sample vessel, such as a capillary, onto the sample holder. Alternatively, the mount may be a body for holding the sample on the sample holder or a cavity within the sample holder. For example, the sample can be held in a cavity or on a plate of the sample holder (e.g., for XRF or XRD analysis in reflection geometry), or can be contained between two foils (e.g., for X-ray analysis in transmission geometry). The particular vessel used will depend, in part, on the type of X-ray analysis measurement to be performed and the type of sample to be analyzed.

[0014] In some embodiments, the holder datum portion is a protrusion and the stage datum portion is a recess for receiving the protrusion, or the stage datum portion is a protrusion and the holder datum portion is a recess for receiving the protrusion.

[0015] The recesses may be of any shape suitable for receiving the protrusions. In some embodiments, the recesses may be notches or grooves (i.e., elongated). The grooves may be straight or curved. In preferred embodiments, the recesses and protrusions may have sloping walls.

[0016] In some embodiments, the sample holder has a central axis and the sample stage comprises: a base including a platform; and a reference assembly including a stage reference portion; may include The datum assembly is positioned facing the platform, and in the aligned configuration, the stage datum portion engages the holder datum portion.

[0017] The sample mount system may include a rotation mechanism for rotating the sample holder about its central axis. The rotation mechanism may allow an operator to adjust the orientation of the sample holder. That is, if the stage reference portion and the holder reference portion are shaped such that the sample holder freely rotates about its central axis when the stage reference portion and the holder reference portion are engaged, the sample holder freely rotates about its central axis while the sample holder and the sample stage are in the aligned configuration. Thus, the rotation mechanism may allow an operator to adjust the orientation of the sample holder while the sample holder and the sample stage are in the aligned configuration.

[0018] The holder reference portion and / or the stage reference portion may include a sloped wall.

[0019] The angled walls can help align the reference portions such that the reference portions are "self-aligning." For example, when the stage reference portion and the holder reference portion are brought closer together, the angled walls can help position the alignment configuration.

[0020] The stage reference portion may include a bearing attached to the reference assembly, and the holder reference portion may include a notch in a surface of the sample holder for receiving the bearing.

[0021] The reference assembly does not have to be located above the sample holder, in which case the notch does not have to be on the top surface of the sample holder, but instead can be on another surface of the sample holder (e.g., the bottom of the sample holder, etc.).

[0022] The shape of the notch may differ from the shape of the bearing, as long as the notch is capable of receiving the bearing, which may be a roller bearing or a ball bearing.

[0023] If either the holder reference portion or the stage reference portion includes a recess (ie, for receiving a corresponding protrusion on the stage reference portion or holder reference portion, respectively), the recess may include sloped walls.

[0024] The walls of the recess can be sloped at an angle less than 80 degrees, for example, between 20 and 60 degrees. The angle between the sloped walls can be obtuse. Thus, the width of the recess can decrease with depth, so that the recess can form a tapered cavity. If the recess is a notch, the walls can be sloped relative to the bottom of the notch. If the recess is a groove, the first and second sidewalls can meet at an apex of the bottom of the groove so that the groove appears triangular in cross section.

[0025] The recess may include curved walls.

[0026] The sample holder may include multiple holder reference portions, and the sample stage may include multiple corresponding stage reference portions. The amount of holder reference portions and stage reference portions does not necessarily have to be equal.

[0027] The sample mount system may include multiple pairs of respective reference portions (ie, multiple pairs of holder reference portions and stage reference portions).

[0028] The sample holder is: a body having a peripheral edge; and Holder alignment part; may further comprise The holder alignment portion is a recess extending inward from the periphery or a protrusion extending outward from the periphery.

[0029] The holder alignment portion can visually assist the user in manually pre-positioning the sample holder, thereby ensuring proper alignment of the sample holder and sample stage so that the stage reference portion and holder reference portion engage with each other to accurately position the sample for analysis. The holder alignment portion can also assist the user in aligning the sample holder with the sample changer for loading the sample onto the platform.

[0030] The sample mounting system is The sample stage may further include a sample changer for loading the sample holder onto the sample stage, the sample changer including a changer alignment portion, the holder alignment portion and the changer alignment portion configured to engage with each other when the sample holder is in an aligned orientation with the sample changer.

[0031] The holder alignment portion may be a protrusion and the changer alignment portion may be a recess for receiving the protrusion, or vice versa.

[0032] In one aspect of the present invention, there is provided a method of mounting a sample on the above sample mounting system, the method comprising: placing the sample holder on the platform; moving the sample holder toward the stage reference portion so that the stage reference portion and the holder reference portion contact; and applying a force to the stage reference portion via the holder reference portion to move the sample holder to an aligned configuration; Includes:

[0033] The method involves: aligning the orientation of the sample holder with the sample changer by placing the sample holder such that the position of the holder alignment portion corresponds to the position of the changer alignment portion, such that the sample holder is in an aligned orientation; With the sample holder in the aligned orientation, inserting the sample holder into a sample changer; and loading the sample holder onto the platform; It may further include:

[0034] The sample changer may be an automatic sample changer, and the method may further include pre-aligning the sample changer with the sample stage so that when the sample holder is inserted into the sample changer in the aligned orientation, the sample changer loads the sample holder onto the platform in a position corresponding to the aligned configuration.

[0035] The holder alignment portion may be a flange and the changer alignment portion may be a recess for receiving the flange, and the step of inserting the sample holder into the sample changer in the aligned orientation may include inserting the flange into the recess. [Brief explanation of the drawings]

[0036] Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which it should be noted that these figures are schematic and are not drawn to scale, and the relative dimensions and proportions of parts of these figures have been shown exaggerated or reduced in size for clarity and convenience in the drawings. [Figure 1] 1 is a schematic cross-sectional view of a sample mounting system for an X-ray analysis instrument, according to one embodiment of the present invention; [Figure 2] FIG. 2 is a schematic plan view of an alternative sample holder for use in the embodiment of FIG. 1. [Figure 3] 1A-1C are schematic cross-sectional views of various stage and holder datums for use in embodiments of the present invention. [Figure 4] 1 is a schematic perspective view of a sample holder according to an embodiment of the present invention; [Figure 5]10A-10C illustrate the interaction between a holder reference portion and a stage reference portion in one embodiment of the present invention. [Figure 6] FIG. 5 is a schematic perspective view of an embodiment including the sample holder of FIG. 4. [Figure 7] FIG. 2 is a schematic plan view of a sample changer of a sample mounting system, according to one embodiment of the present invention. [Figure 8] 1 illustrates a method of using a sample mount system according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0037] Typically, an X-ray analysis instrument includes an X-ray source, an X-ray detector, and a sample support, and may also include a goniometer to determine the angular position of the X-ray detector and / or the X-ray source. Figure 1 shows a schematic diagram of a sample mounting system 10 for an X-ray analysis instrument, according to one embodiment of the present invention.

[0038] The sample mounting system 10 includes a sample holder 1 and a sample stage 3 having a platform 7 for supporting the sample holder 1. In this embodiment, the sample is contained in a capillary 5, which is secured to the sample holder 1 by a mount 9 on the top surface of the sample holder 1. The sample stage 3 also includes a base 8 and a reference assembly 11 disposed above the base 8 such that the top surface of the sample holder 1 faces the reference assembly 11. The sample stage 3 further includes a rotation mechanism 17 integrated into the base 8. The rotation mechanism 17 is configured to rotate the sample holder 1 about its central Z-axis 19 when the sample holder is on the platform 7. The rotation mechanism can also be configured to rotate the capillary along its central longitudinal axis (X-direction in FIG. 1 ).

[0039] As illustrated by the arrows, the height of the platform 7 can be adjusted to change the position of the sample relative to the reference assembly 11 (i.e., to change the position of the sample along the Z axis). This can help allow a user to conveniently exchange sample holders 1, for example, when changing samples. If the sample mount system 10 is used in an X-ray apparatus that includes a goniometer, the sample mount system 10 is located at the center of the goniometer circle. The reference assembly 11 is then fixed in place, providing a convenient reference point to refer to when adjusting the position of the platform 7 and / or sample holder 1 along the Z axis.

[0040] In addition to aligning the sample holder 1 along the Z axis, the inventors have recognized that it is useful to be able to position and / or orient the sample holder 1 in other directions. That is, it is useful to be able to position the sample holder 1 in a convenient and repeatable manner in a plane perpendicular to the height direction (i.e., along the X and / or Y directions). In addition to positioning the sample holder 1 in a repeatable manner in the XY plane, it may also be useful to orient the sample holder 1 in a repeatable manner (i.e., to reduce / avoid rotation of the sample about the central Z axis relative to a reference orientation).

[0041] Displacement of the sample holder (and therefore the sample) in a direction along the incident beam path can result in an apparent shift in the position of the measured diffraction peak. With reference to Figure 1, the displacement along the beam path is the displacement in the Y direction, or, if the incident beam path is in the XY plane, the displacement along the beam path is the displacement along the component of the incident beam path in the Y direction. Apparent shift refers to the change in the position of the measured diffraction peak when the same sample is analyzed in subsequent measurements, and the sample is displaced between the two measurements. That is, if the sample is first analyzed in its original position, then displaced along the Y axis, and analyzed again in the displaced position, the diffraction peak obtained in the displaced position will appear shifted compared to the diffraction results obtained with the sample holder 1 in its original position. Additionally, the amount of peak shift resulting from the displacement varies with the diffraction angle. Sample displacements of only a few tens of micrometers (e.g., 100 μm) can result in a peak shift. Because the positions of the diffraction peaks are used to identify the components / crystalline phases present in the sample, the shift in peak position can make it more difficult to accurately interpret the results of the diffraction analysis. This is generally an issue in any application where measured data is compared to a standard to identify the components / crystalline phases present in a sample. For example, this can be an issue when diffraction analysis is performed by comparing results to a database of X-ray diffraction patterns or when using reference standards. Therefore, it is desirable for the sample holder to be placed on the platform in a repeatable manner.

[0042] This is not only an issue for X-ray analysis performed in transmission geometry. For example, for X-ray diffraction analysis performed in reflection mode, or for X-ray fluorescence (XRF) analysis of a sample, the position of the sample in the XY plane (e.g., the plane of the sample's surface to be illuminated) is important if it is desired to illuminate only a portion of the illuminated surface. For example, positioning in the plane of the illuminated surface (when the sample is mounted for reflection geometry or XRF analysis, the illuminated surface is in the XY plane in FIG. 1) may be required to ensure that only certain portions of a (heterogeneous) sample are analyzed.

[0043] Accurate and reproducible sample positioning can also be an issue when X-ray computed tomography (CT) measurements are performed. For CT measurements, the intensity transmitted through the sample is typically measured by a 2D detector. By measuring the intensity for many sample orientations (e.g., by rotating the sample around the z-axis) and using a reconstruction algorithm, the 3D morphology of the sample can be obtained. Accurate and reproducible sample positioning is particularly problematic when an analyst wants to correlate CT data with data from XRD or XRF measurements on a portion of the sample. Similarly, accurate and reproducible sample positioning is also problematic when an analyst wants to correlate CT data with any other analyses on the same sample, and when the sample needs to be moved or remounted between measurements, for example, when several samples are measured in a batch using a sample changer. Reproducible mounting in the rotational plane is also necessary when several CT measurements must be merged. This may be necessary, for example, when a sample is too large to allow sufficient analysis in a single CT scan.

[0044] Additionally, sample rotation in the XY plane can make it more difficult to accurately interpret the results of XRD, CT, and / or XRF analysis. In XRD measurements performed in transmission geometry, the sample can be positioned so that the irradiated surface is perpendicular to the incident X-ray beam. When the sample is rotated, one portion of the sample may be placed relatively closer to the X-ray detector compared to its initial position, and another portion of the sample may be placed relatively farther from the X-ray detector. This means that diffraction from one portion of the sample is detected at a relatively high angle, and diffraction from another portion of the sample is detected at a relatively low angle. Therefore, diffraction peaks measured when the sample is in a rotated orientation appear broader than diffraction peaks measured with the sample in its initial position. Therefore, it is desirable to be able to place the sample holder on the platform in the same orientation for each measurement.

[0045] In an embodiment of the present invention, the sample mount system includes a stage reference portion 13 and a holder reference portion 15, which are arranged to cooperate with each other when the sample holder and the reference assembly are aligned in the XY plane. In this manner, the stage reference portion 13 and the holder reference portion 15 can assist a user in determining the precise position (position and / or orientation) of the sample holder 1 on the platform 7. In FIG. 1 , the sample stage 3 includes two stage reference portions 13, each of which is a protrusion 13, and two corresponding holder reference portions 15. The holder reference portions 15 are recesses for receiving the stage reference portions 13. The protrusions 13 protrude toward the platform 7. When the sample holder 1 is placed on the platform 7 with the protrusions 13 aligned with the recesses 15, the protrusions 13 can be mated with the recesses 15 by moving the platform toward the reference assembly 11 until the tip of the protrusion contacts the bottom of the recess. In this arrangement, the sample holder 1 is in an aligned configuration. By providing an arrangement in which the holder reference portion 15 and the reference assembly 11 can mate only when the sample holder 1 is in a specific position relative to the reference assembly 11, the sample mount system 10 can help the user position the sample holder 1 in a repeatable manner. By supporting repeatable positioning of the sample, the sample mount system 10 can help achieve reliable X-ray analysis results.

[0046] 1, the holder reference portion is provided on the top surface of the sample holder, but it may alternatively be provided in a different location. Similarly, the stage reference portion should be positioned above the sample holder, facing the top surface of the sample holder. For example, the holder reference portion can be provided on the bottom of the sample holder, and the stage reference portion can be located below the sample holder.

[0047] In the embodiment illustrated in FIG. 1, the protrusions and recesses are cuboid-shaped (they are shown as rectangles in cross section). However, other shapes can be used. FIG. 2 shows various options for the shape, in plan view, of the holder reference portion 15 in FIG. 1. Each of these recesses can be used with a sample holder having a correspondingly shaped protrusion. In each example, the sample holder or the reference assembly may include the recess, and the other of the sample holder and the reference assembly may include the protrusion (or projection).

[0048] 2A, the holder reference portion 15 is circular. If the recess is circular, the protrusion 13 can engage with the recess 15 in any orientation when the sample holder 1 is aligned with the reference assembly 11 in the XY plane. That is, the protrusion can engage with the reference assembly 11 even while the sample holder 1 rotates about its central axis (i.e., even while the orientation of the sample holder changes). The protrusion 13 may also be circular in shape or a segment of a circle. In either case, the protrusion 13 and the recess 15 can engage only when the sample holder is placed on a platform in the XY plane so as to be aligned with the reference assembly 11. In some embodiments, the reference assembly 11 may include multiple concentric protrusions or projections 13, and the sample holder may include multiple corresponding circular recesses 15 for receiving the protrusions or projections 13.

[0049] In FIG. 2B, sample holder 1 includes multiple recesses, each of which is a circular segment. Some examples of protrusions (or projections) that can be used in this arrangement are circular protrusions or circular segments. The pattern may be circularly symmetric so that one or more protrusions can engage the reference assembly at multiple different sample holder orientations. In another example, the sample holder may include recesses that are circular segments, and reference assembly 11 may include protrusions or projections that are smaller circular segments (i.e., the segments subtend a smaller angle). In this arrangement, the orientation of the sample holder in the aligned configuration may be limited.

[0050] In Figure 2C, the sample holder includes two holder reference portions with different shapes. The reference assemblies can have corresponding patterns, for example. One of the holder reference portions is a linear protrusion, and the other is a small rounded mass. In this arrangement, the sample holder and reference assembly can only engage when the sample holder is in one orientation, so the orientation of the sample holder is limited in the aligned configuration.

[0051] Although the stage and holder datum portions are shown in FIG. 1 as having a constant width, each may generally have a non-constant width and a tapered profile. FIG. 3 shows some example profiles for corresponding stage and holder datum portions in cross section. FIG. 3A shows a wedge-shaped protrusion 13 with a V-shaped recess 15. The V-shaped recess 15 is defined between two sidewalls that meet at the apex of the recess 15's bottom. The recess may be a groove (i.e., elongated) or a notch (the groove width may be greater than the groove length). Sloped walls can assist in positioning the alignment feature. In particular, the sloped walls can help the sample holder self-align with the stage / holder datum portion when the recess and protrusion are pressed together. FIG. 3B shows a protrusion 13 with a rounded tip with a groove 15 having a curved bottom. FIG. 3C shows another example of a recess 15 defined between two sloped walls.

[0052] 3 shows an example in which the holder reference portion and the stage reference portion have the same / similar (i.e., complementary) shapes, this is not required. The holder reference portion may have a different shape than the stage reference portion, as long as the reference portions contact each other at two opposing contact points.

[0053] FIG. 4 illustrates a sample holder 20 according to another embodiment. The sample holder has a circular bottom 21 and includes two walls 22 protruding from the top surface of the bottom 21. The two walls face each other and define a channel 23 extending diametrically across the bottom 21 of the sample holder 20. A mount 29 is positioned to hold a sample container 25 across the channel. The walls 22 include notches 35 disposed around the periphery of the sample holder 20. Each notch 35 has a radially extending bottom. Each notch 35 is defined between two walls. The walls are inclined at an acute angle (e.g., approximately 45 degrees) relative to a plane containing the top surface of the wall. The angle between the two walls may be an obtuse angle, i.e., greater than 90 degrees. Providing an inclined surface on the notch can assist the user in positioning the alignment configuration. In one embodiment, the sample holder is used with a fiducial assembly including one or more wedge-shaped protrusions or projections corresponding to the three notches 35. Preferably, the reference assembly includes three or fewer protrusions. In an alternative embodiment, the reference assembly includes one or more corresponding bearings (eg, roller bearings, ball bearings, etc.).

[0054] FIG. 5 illustrates the interaction between the bearing 33 and the notch 35 according to one embodiment of the present invention. To load the sample holder 1, 20 onto the sample stage 3 for analysis by an X-ray analyzer, the sample holder is placed on a platform. An operator can position the sample holder in approximately the appropriate orientation depending on the X-ray analysis to be performed. That is, the operator can position the sample holder on the platform so that the position of the notch 35 corresponds approximately (but not necessarily exactly) to the position of the bearing 33. The platform is then lifted, and the sample holder 1, 20 is oriented toward the reference assembly. As the top surface of the sample holder contacts the bearing 35 and the platform is moved toward the reference assembly, the bearing 35 rotates, and the resulting force pushes the sample holder into a position where the notch receives the bearing (i.e., the sample holder moves into an aligned configuration). In this way, the sample holder and the reference assembly cooperate to more precisely align the sample holder with the reference assembly. This avoids the need for an operator to spend time precisely aligning the sample holder, allowing X-ray analysis of the sample to be performed in a more efficient manner. Additionally, by facilitating alignment of the sample holder with the X-ray device, the sample holder can be conveniently loaded without compromising the reliability of the X-ray analysis results.

[0055] FIG. 6 shows the sample holder of FIG. 4 together with a corresponding reference assembly 31. The sample holder 20 is placed on a platform (not shown) and can be rotated about its central axis by a rotation mechanism located below the platform. The reference assembly 31 includes a plurality of stage reference portions 33 arranged to contact the upper surface of the sample holder 20. The stage reference portions 33 are bearings (e.g., roller bearings or ball bearings). Each bearing has a cylindrical body that can rotate about a fixed central axis. As shown in FIG. 6, when the sample holder 20 and the reference assembly 31 are aligned, the bearings are received in corresponding notches 35.

[0056] In some embodiments, the reference assembly 31 can be positioned so that the sample container is centered on the goniometer when the bearing 33 is received in the notch 35. In this way, the bearing 33 can also provide a height reference for the sample.

[0057] In some embodiments, the sample holder can be manually replaced or removed by an operator. Alternatively, the X-ray device may include an automated sample changer for removing and replacing the sample holder on the sample stage. Using a sample changer can contribute to improved efficiency. However, conventional sample changers generally cannot repeatably position the sample holder on the platform within the spatial tolerance required to avoid possible analysis errors caused by sample displacement. Therefore, even when the sample holder is placed on the platform by an automated system, it is important to ensure that the sample holder and the reference assembly are properly aligned. The sample holder may be pre-aligned to the sample changer to ensure that the sample holder is properly oriented on the sample changer to enable alignment of the reference assembly and the sample holder after the sample holder is loaded onto the platform.

[0058] FIG. 7 shows a sample changer 50 along with the sample holder 20 of FIG. 4. The sample holder 40 includes a flange 42 that projects outward from a body 58 of the sample holder 20. The sample changer includes a chamber for receiving the sample holder and a recess 52 for receiving the flange 42. When the sample holder 40 is stacked on the sample changer, the recess 52 is positioned to receive the flange. In this way, an operator can conveniently ensure that the sample holder 40 is in the proper orientation on the sample changer 50.

[0059] Figure 8 illustrates a method of using a sample mounting system according to one embodiment of the present invention. The first step of the method shown in Figure 8 is optional; pre-alignment step 60 may be performed if the sample mounting system includes a sample changer. If the sample mounting system does not include an automatic sample changer, this step is not included.

[0060] In a pre-aligning step 60, the sample holder is placed in the same changer and oriented to align with the sample changer, i.e., the sample holder is oriented so that the holder alignment portion engages with the changer alignment portion.

[0061] Next, in a first loading step, the sample holder is placed on the platform of the sample stage. In some embodiments, the sample holder can be loaded manually. However, if the sample mounting system includes a sample changer, the sample changer can automatically load the sample onto the platform. The sample holder is loaded onto the platform so that it is in approximately the correct position and orientation. In a subsequent loading step 64, the platform is moved toward the reference assembly to orient the stage reference portion toward the top surface of the sample holder. In a further step 66, the stage reference portion and sample holder are pressed together (e.g., as shown in FIG. 5 ), self-aligning the stage reference portion and holder reference portion and further moving the sample holder into a configuration in which the stage reference portion and holder reference portion engage with each other.

[0062] Those skilled in the art will understand that various modifications can be made to the described embodiments while still falling within the scope of the present invention.

[0063] In FIG. 1 , a capillary is used to contain the sample. The capillary may be used, for example, to allow convenient analysis using X-ray diffraction analysis in a transmission geometry. However, the sample loading system 10 can be used with other types of containers. For example, the sample can be held in a cavity or on a plate of a sample holder (e.g., for XRF or XRD analysis in a reflection geometry), or can be contained between two foils (e.g., for X-ray analysis in a transmission geometry). The particular container used will depend, in part, on the type of X-ray analysis measurement to be performed and the type of sample to be analyzed.

[0064] A mount may be a mechanism for attaching a sample vessel, such as a capillary, onto a sample holder, or it may be a body or cavity within a sample holder for holding a sample on the sample holder.

[0065] The holder reference portion and the stage reference portion may or may not have the same shape (in plan and / or cross section).

[0066] A sample mount system may include any number of pairs of stage and holder reference portions. For example, the embodiment described in connection with Figure 4 may not have three pairs of stage and holder reference portions.

[0067] The stage datum portion does not necessarily have to be a protrusion; it may instead be a recess. Similarly, the holder datum portion does not necessarily have to be a recess; it may instead be a protrusion.

[0068] The holder alignment portion does not necessarily have to be a protrusion; instead it may be a recess. Similarly, the changer alignment portion does not necessarily have to be a recess; instead it may be a protrusion.

[0069] The sample holder need not be designed to hold the sample in a position suitable for X-ray diffraction in transmission geometry, but instead can be designed to hold the sample in a position suitable for other types of X-ray analysis, such as small spot X-ray fluorescence or X-ray diffraction in reflection geometry on heterogeneous samples, X-ray computed tomography, or a combination of these techniques.

[0070] The sample stage may or may not include a rotation mechanism. If the sample mounting system (e.g., sample stage, etc.) includes a rotation mechanism, the rotation mechanism may be motor-driven. The sample mounting system (e.g., sample stage, etc.) may not include a rotation mechanism. Rotation of the sample holder may not be required at all or may be performed manually.

[0071] The recesses may be grooves (ie, elongated) or notches (ie, non-elongated).

[0072] The recess and protrusion may have the same shape or different shapes, so long as the pair can engage with each other.

[0073] The one or more holder datum portions do not necessarily have to be on the top surface of the sample holder, but instead can be on the bottom or side of the sample holder. Similarly, the one or more stage datum portions do not necessarily have to be on a datum assembly opposite the top surface of the sample holder, but can be located anywhere on the stage as long as they can engage with the sample holder. For example, if the sample holder includes a holder datum portion on its bottom, one or more stage datum portions can be located on the surface of the stage that supports the sample (i.e., on the platform).

Claims

1. 1. A sample mounting system for an X-ray analysis instrument, comprising: a sample holder including a mount, the mount securing a sample to an upper surface of the sample holder, the sample holder further including a holder reference portion; a sample stage including a platform for supporting the sample holder, the sample stage including a stage reference portion for cooperating with the holder reference portion to position the sample holder on the platform; Including, the sample holder and the sample stage have an alignment configuration in which the sample holder is placed on the platform such that the stage reference portion and the holder reference portion engage with each other; The sample holder has a central axis, and the sample stage has: a base including the platform; a reference assembly including the stage reference portion; Including, the reference assembly is positioned facing the platform, and in the aligned configuration, the stage reference portion engages the holder reference portion; A sample mount system, wherein the stage reference portion includes a bearing attached to the reference assembly, and the holder reference portion includes a notch in a top surface of the sample holder for receiving the bearing.

2. 2. The sample mount system of claim 1, wherein the sample holder has a central axis, and the stage reference portion and the holder reference portion are configured such that, in the aligned configuration, engagement of the stage reference portion and the holder reference portion holds the sample holder such that rotation of the sample holder about the central axis is limited or prevented.

3. the holder reference portion is a protrusion and the stage reference portion is a recess for receiving the protrusion; or the stage reference portion is a protrusion, and the holder reference portion is a recess for receiving the protrusion; 3. The sample mount system according to claim 1 or 2.

4. 4. The sample mount system of claim 1, wherein the holder reference portion and / or the stage reference portion comprises an inclined wall.

5. 5. A sample mount system according to claim 3, wherein the recess includes a sloped wall.

6. The sample mount system of claim 5 , wherein the recess has curved sidewalls.

7. 7. The sample mount system of claim 1, wherein the sample holder includes a plurality of holder reference portions and the sample stage includes a plurality of corresponding stage reference portions.

8. The sample holder is a body having a periphery; a holder alignment portion; further comprising 8. The sample mount system of claim 1, wherein the holder alignment portion is a recess extending inward from the periphery or a protrusion extending outward from the periphery.

9. 9. The sample mounting system of claim 8, further comprising a sample changer for loading the sample holder onto the sample stage, the sample changer including a changer alignment portion, the holder alignment portion and the changer alignment portion configured to engage with each other when the sample holder is in an aligned orientation with the sample changer.

10. 10. The sample mount system of claim 9, wherein the holder alignment portion is a protrusion, and the changer alignment portion is a recess for receiving the protrusion.

11. 11. A method of mounting a sample on a sample mount system according to any one of claims 1 to 10, comprising the steps of: placing the sample holder on the platform; moving the sample holder toward the stage reference portion so that the stage reference portion and the holder reference portion contact; applying a force to the stage reference portion via the holder reference portion to move the sample holder to the aligned configuration; A method comprising:

12. 10. The sample mount system according to claim 9, wherein the method further comprises: aligning the orientation of the sample holder with the sample changer by placing the sample holder such that the position of the holder alignment portion corresponds to the position of the changer alignment portion, such that the sample holder is in an aligned orientation; inserting the sample holder into the sample changer with the sample holder in the aligned orientation; loading the sample holder onto the platform; The method of claim 11 further comprising:

13. 13. The method of claim 12, wherein the holder alignment portion is a flange and the changer alignment portion is a recess for receiving the flange, and the step of inserting the sample holder into the sample changer in the aligned orientation includes inserting the flange into the recess.

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