X-ray analyzers that can be adapted, methods for controlling X-ray analyzers, and computer program products.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- マルバーンパナリティカルビーヴィ
- Filing Date
- 2022-07-29
- Publication Date
- 2026-07-30
Smart Images
Figure 0007897735000007 
Figure 0007897735000008 
Figure 0007897735000009
Abstract
Description
Technical Field
[0001] The present invention relates to an apparatus and method for X-ray analysis. Each embodiment particularly relates to an X-ray analysis apparatus for executing a plurality of X-ray analysis applications. More specifically, each embodiment relates to an X-ray analysis apparatus for analyzing a sample by X-ray diffraction, X-ray scattering, or X-ray fluorescence.
Background Art
[0002] Generally, an X-ray generating device (for example, an X-ray tube) includes a cathode and an anode. The cathode is arranged to irradiate the surface of the anode with an electron beam, and X-rays are emitted from the irradiated area. The irradiated area of the anode is known as the focal spot.
[0003] Some X-ray tubes have a rotating anode, which rotates during operation. Also, some other X-ray tubes have a stationary anode, which remains stationary during operation.
[0004] Generally, an X-ray tube includes a housing having a cathode and an anode therein. Depending on the configuration, the surface of the anode irradiated with the electron beam is inclined obliquely with respect to the electron beam. In such a configuration, the size of the focal spot (known as the "effective focal spot") as seen from a measurement device that measures the X-ray beam emitted from the X-ray tube is different from the size of the irradiated area of the anode. The size of the effective focal spot can be measured in accordance with European standard EN12543:1999 (Parts 1 to 5).
[0005] In the case of a conventional solid anode X-ray tube, in order to avoid damage to the anode, it is necessary to keep the surface temperature of the operating anode much lower (for example, more than 100 °C) than the melting point of the anode. For this reason, there may be a trade-off between the area of the effective focal spot and the setting of the optimum operating power. For example, in some applications, it is desirable to use a focal spot with a small area. To accommodate this, the maximum power suitable for an X-ray tube with a small focal spot is relatively lower than that of an X-ray tube with a larger focal spot while avoiding damage to the anode.
[0006] The optimal operating power setting for an X-ray tube is determined by a combination of the voltage drop between the anode and cathode (operating voltage, kV) and the emission current (mA), i.e., the flow of electrons from cathode to anode, and is generally determined as part of the manufacturing process. Various factors that can affect the behavior of the electron beam are considered when setting the optimal operating power. One such factor is the internal geometry of the X-ray tube surrounding the anode and cathode. Therefore, each individual X-ray tube generally has a corresponding operating power, which is determined during manufacturing (for example, an X-ray tube may be a "50W X-ray tube"). This allows the user to operate the X-ray tube in a way that ensures both accurate function and reliability and durability.
[0007] Users generally select an X-ray tube for their X-ray analyzer based on the specific X-ray analysis application they intend to perform. In this way, users can select an X-ray tube suitable for the relevant application. Some X-ray analysis applications, such as powder diffraction on large samples, can be performed using an X-ray beam with a large focal point, enabling relatively high intensity measurements. However, other X-ray analysis applications require the use of a small-focus X-ray tube (for example, an X-ray tube with an effective focal point size of less than 300 μm). A small focal point means the X-ray tube operates at a relatively low power, resulting in relatively low intensity measurements. For example, X-ray diffraction applications such as two-dimensional small-angle X-ray scattering (2DSAXS), grazing incidence small-angle X-ray scattering (GISAXS), and fine diffraction measurements are generally performed using small-focus X-ray tubes (X-ray tubes with an effective focal point size of less than 100 μm). Alternatively, these applications can be made feasible by using an X-ray tube with a larger effective focal spot in combination with a collimator optical element. This collimator optical element reduces the size and intensity of the X-ray beam before it is irradiated onto the sample.
[0008] Small-focus X-ray tubes are generally directly coupled (i.e., fixed) to the optical elements required for a particular X-ray analysis application. [Overview of the project] [Problems that the invention aims to solve]
[0009] It would be desirable to be able to perform multiple different types of X-ray analysis applications using a single X-ray analyzer, while minimizing the need to reconfigure the analyzer. [Means for solving the problem]
[0010] According to one aspect of the present invention, an X-ray analyzer is provided that performs a plurality of X-ray analysis applications for analyzing a sample by measuring at least one of X-ray diffraction and X-ray fluorescence. The X-ray analyzer is An X-ray source for irradiating a sample with X-rays, comprising a solid anode and a cathode that emits an electron beam, A focusing device that concentrates the electron beam onto the anode, A control device configured to receive X-ray analysis application information and to control an X-ray analyzer to selectively operate in either a first X-ray analysis mode or a second X-ray analysis mode based on this X-ray analysis application information; Equipped with, In the first X-ray analysis mode, the X-ray source is controlled to operate at a first operating power and a first operating voltage, and the effective focal spot size is less than 100 μm. In the second X-ray analysis mode, the X-ray source is controlled to operate with a second operating power and a second operating voltage, where the second operating power is greater than the first operating power, and the effective focal area is larger than the effective focal area in the first X-ray analysis mode.
[0011] The control unit is configured to control the X-ray analyzer to operate in either the first X-ray analysis mode or the second X-ray analysis mode. The control unit may include an input unit for receiving information about the X-ray analysis application. The X-ray analysis application may be an X-ray diffraction application, an X-ray fluorescence application, or a combination of both X-ray diffraction and X-ray fluorescence analysis.
[0012] The operating voltage refers to the high voltage applied between the anode and cathode to move electrons from the cathode to the anode. The first operating voltage may be equal to or different from the second operating voltage. In some embodiments, the first operating voltage is 60 kV and the second operating voltage is 60 kV. In some embodiments, the effective focal size of the first X-ray analysis mode is smaller than the effective focal size of the second X-ray analysis mode. X-ray analysis application information refers to information about the type of X-ray analysis application to be performed. X-ray analysis application information may also refer to information about the incident beam X-ray optical elements used in the X-ray analysis application. For example, the control device may be configured to operate the X-ray analyzer in the first or second X-ray analysis mode based on information that identifies the X-ray optical elements. Alternatively, the control device may be configured to operate the X-ray analyzer in the first or second X-ray analysis mode based on other information about the X-ray optical elements (for example, whether the X-ray optical elements are positioned to receive the X-ray beam).
[0013] In some embodiments, the X-ray analysis application information may include information that identifies the X-ray analysis application. In some embodiments, the X-ray analysis application information may include information about the sample, such as the size of the sample.
[0014] The size of the effective focal spot is determined by the larger of the effective focal spot's length (l) or width (w). The area of the effective focal spot is the product of the measured length and the measured width. For a nearly circular focal spot, the diameter is measured to determine the length and width.
[0015] The anode may be a stationary anode. That is, in contrast to a rotating anode, which rotates around its axis during operation, the anode remains stationary during operation.
[0016] The effective focus is the focal point observed in an X-ray beam, and may or may not have dimensions equal to the irradiated area of the anode.
[0017] In some embodiments, the X-ray source has an effective focal spot size of less than 55 μm in the first X-ray analysis mode and an effective focal spot size of greater than 60 μm in the second X-ray analysis mode.
[0018] In some embodiments, the effective focus in the first X-ray analysis mode may be substantially circular (or square). In these embodiments, the diameter (or length) of the effective focus is less than 55 μm. In the second X-ray analysis mode, the effective focus may be "linear," i.e., rectangular or elliptical. The width and length of this effective focus may exceed 60 μm, as long as the area of the effective focus in the second X-ray analysis mode is greater than the area of the effective focus in the first X-ray analysis mode. Alternatively, in the second X-ray analysis mode, both the width and length of the effective focus may exceed 60 μm.
[0019] The X-ray analyzer may further include a first replaceable X-ray optical element positioned to receive X-rays from an X-ray source.
[0020] The first replaceable X-ray optical element may be placed between the X-ray source and the sample. In this regard, the X-ray optical element is not fixed to the X-ray source and is therefore replaceable.
[0021] The control device may be configured to receive information identifying a first replaceable X-ray optical element. The control device may also be configured to operate the X-ray analyzer in either a first X-ray analysis mode or a second X-ray analysis mode based on the information identifying the first replaceable X-ray optical element.
[0022] The X-ray analysis application information may be the name of the X-ray analysis application, and this name may correspond one-to-one with the X-ray optical element used for the X-ray analysis application. In this way, the X-ray optical element may be specified by the name of the X-ray analysis application. The replaceable optical element may be configured to be manually replaced. The X-ray analysis apparatus may further include a second replaceable X-ray optical element. The control device may be configured to operate the X-ray analysis apparatus in either the first X-ray analysis mode or the second X-ray analysis mode based on information specifying the second replaceable X-ray optical element.
[0023] In some embodiments, the effective focal spot may have an aspect ratio greater than 2.0 in both the first X-ray analysis mode and the second X-ray analysis mode. The control device may be configured to receive sample information and to operate the X-ray analysis apparatus in the first X-ray analysis mode or the second X-ray analysis mode based on this sample information.
[0024] This sample information may relate to the dimensions of the sample, or the type of sample to be analyzed, or the type of analysis to be performed on the sample. The aspect ratio is the ratio of the size of the effective focal spot to the other of the length and the width. For example, when the size of the effective focal spot is determined by the length of the focal spot, the aspect ratio is the ratio of the length to the width.
[0025] In some embodiments, in the first X-ray analysis mode, the size of the effective focal spot may be less than 40 μm. The aspect ratio of the effective focal spot may be less than 1.5. The first operating power may be less than 50 W.
[0026] In some cases, the size of the effective focal spot may be less than 25 μm. This X-ray analysis mode can be adapted for use in combination with a multilayer two-dimensional mirror, which is used in X-ray analysis applications such as two-dimensional small-angle X-ray scattering (2DSAXS), grazing-incidence small-angle X-ray scattering (GISAXS), microdiffraction, and computed tomography.
[0027] In some embodiments, in the second X-ray analysis mode, the size of the effective focal spot may be larger than that of the first X-ray analysis mode, and may exceed 60 μm. The aspect ratio of the effective focal spot may be less than 1.5. The second operating power may exceed 50 W.
[0028] This mode can be particularly adapted for use in combination with monocapillary or polycapillary licolimeters, which are available for use in X-ray analysis applications such as stress and texture measurement.
[0029] In some embodiments, in the first X-ray analysis mode, the effective focus may have an aspect ratio of less than 1.5. In the second X-ray analysis mode, the effective focus may be elongated and have an aspect ratio greater than 2.0.
[0030] In some embodiments, in the second X-ray analysis mode, the effective focal size may be greater than 60 μm, and the second operating power may be greater than 50 W. This mode can be particularly adapted for use in combination with a collimator slit, a one-dimensional mirror, or a hybrid monochromator.
[0031] In some embodiments, the effective focal size in the second X-ray analysis mode may be 100 μm, and the second operating power may be 100 W or more. Therefore, in the second X-ray analysis mode, the X-ray source can operate with an operating power significantly higher than that of a typical X-ray tube capable of forming a microfocus.
[0032] In some embodiments, the X-ray analyzer is A sample stage that supports a sample, wherein the X-ray source is positioned to irradiate the sample with X-rays directed along the incident beam path, A detector positioned to receive X-rays scattered by or emitted from a sample, It may also be provided with the following:
[0033] Therefore, X-ray analyzers are configured for XRF analysis, X-ray scattering analysis, XRD analysis, computed tomography, or X-ray imaging.
[0034] The X-ray analyzer may include a first replaceable X-ray optical element. The X-ray analyzer may further include a first actuator configured to move the first replaceable X-ray optical element between an in-beam position and an out-beam position, where the in-beam position is the position when the first replaceable X-ray optical element is located within the incident beam path, and the out-beam position is the position when the first replaceable X-ray optical element is located outside the incident beam path. In this case, the control device is configured to receive information that identifies the position of the first replaceable X-ray optical element and to operate the X-ray analyzer in a first X-ray analysis mode or a second X-ray analysis mode based on the position of the first replaceable X-ray optical element.
[0035] The X-ray analyzer may further include a second replaceable X-ray optical element different from the first replaceable X-ray optical element. The X-ray analyzer may be configured to move the second replaceable X-ray optical element between an in-beam position where the second replaceable X-ray optical element is located within the incident beam path and an out-beam position where the second replaceable X-ray optical element is located outside the incident beam path. The control device may be configured to receive information that identifies the position of the second X-ray optical element and to operate the X-ray analyzer in a first or second X-ray analysis mode based on the position of the second replaceable X-ray optical element. This information may be input by the user or sent to the control device by a sensor configured to determine whether at least one of the optical elements is in the in-beam position. The control device may be configured to operate the X-ray analyzer in a first X-ray analysis mode when the first replaceable X-ray optical element is in its beam position and the second replaceable X-ray optical element is out of its beam position, and to operate the X-ray analyzer in a second X-ray analysis mode when the second replaceable X-ray optical element is in its beam position and the first replaceable X-ray optical element is out of its beam position.
[0036] According to one aspect of the present invention, a method for controlling an X-ray analyzer as described above is provided. This method is The steps include: the control unit receiving X-ray analysis application information, Based on this X-ray analysis application information, the step of selecting either the first X-ray analysis mode or the second X-ray analysis mode, The steps include controlling the X-ray source to operate in the selected mode, Includes, In the first X-ray analysis mode, the X-ray source is controlled to operate at a first operating power, and the effective focal spot size is less than 100 μm. In the second X-ray analysis mode, the X-ray source is controlled to operate at a second operating power higher than the first operating power, and the area of the effective focal spot is larger than the area of the effective focal spot in the first X-ray analysis mode.
[0037] Information identifying the X-ray analysis application may include information identifying a first replaceable X-ray optical element, or information identifying the location of at least one of the first replaceable X-ray optical element and the second replaceable X-ray optical element.
[0038] In some embodiments, the X-ray source may have an effective focal spot size of less than 55 μm in the first X-ray analysis mode, and an effective focal spot size of more than 60 μm in the second X-ray analysis mode.
[0039] The method may include the steps of receiving information to identify a first replaceable X-ray optical element, and controlling the X-ray analyzer to operate in a first X-ray analysis mode or a second X-ray analysis mode based on the information to identify the first replaceable X-ray optical element.
[0040] The effective focus may have an aspect ratio greater than 2.0 in both the first and second X-ray analysis modes. The method may include the steps of receiving sample information and controlling the X-ray analyzer to operate in either the first or second X-ray analysis mode based on this sample information.
[0041] In the first X-ray analysis mode, the size of the effective focus may be less than 40 μm. The aspect ratio of the effective focus may be less than 1.5. The first operating power may be less than 50 W.
[0042] In the second X-ray analysis mode, the size of the effective focal spot is larger than in the first X-ray analysis mode, and may exceed 60 μm. The aspect ratio of the effective focal spot may be less than 1.5. The second operating power may exceed 50 W.
[0043] In the first X-ray analysis mode, the effective focus may have an aspect ratio of less than 1.5. In the second X-ray analysis mode, the effective focus may be elongated and may have an aspect ratio greater than 2.0.
[0044] In the second X-ray analysis mode, the effective focal spot size may be greater than 60 μm. The second operating power may be greater than 50 W.
[0045] The effective focal size in the second X-ray analysis mode may be greater than 100 μm. The second operating power may be 100 W or more.
[0046] The X-ray source may irradiate the sample with X-rays directed along the incident beam path. The detector may receive X-rays scattered by or emitted from the sample.
[0047] The control device may receive information that identifies the position of the first replaceable X-ray optical element. The control device may also control the X-ray analyzer to operate in either the first X-ray analysis mode or the second X-ray analysis mode based on the position of the first replaceable X-ray optical element.
[0048] According to one aspect of the present invention, a computer program product is provided comprising a tangible, non-temporary computer-readable medium storing a plurality of program instructions. These program instructions cause the X-ray analyzer described above to perform the steps of the method described above.
[0049] The program instructions may cause the X-ray analyzer to execute any of the methods described above.
[0050] Next, embodiments of the present invention will be described with reference to the accompanying drawings. [Brief explanation of the drawing]
[0051] [Figure 1] This is a schematic diagram showing an X-ray analyzer in one embodiment of the present invention. [Figure 2] This is a schematic diagram showing an X-ray analyzer in another embodiment of the present invention. [Figure 3] This is a schematic diagram illustrating the exemplary shapes of the effective focus for various modes of an X-ray analyzer. [Figure 4]This figure shows an X-ray analysis method according to one embodiment of the present invention. [Figure 5] This diagram shows the configuration for measuring the size of the effective focal spot of an X-ray tube. [Figure 6] This figure shows a line scan of the object under test performed in the longitudinal direction to measure the length of the effective focal point. [Modes for carrying out the invention]
[0052] It should be noted that these figures are illustrative and not drawn to scale. Some of the relative dimensions and proportions in these figures are exaggerated or reduced for clarity and convenience in the drawings.
[0053] Figure 1 shows an X-ray analyzer 1 comprising an X-ray source 3 and a control device 5. Although not shown in Figure 1, it will be understood that the X-ray analyzer 1 may further include a sample stage for supporting the sample to be analyzed and an X-ray detector.
[0054] Referring to Figure 1, the X-ray source 3 (i.e., the X-ray tube) has a solid anode 7 and a cathode 9, which are enclosed in a sealed housing 11. The housing 11 has a window 13, which is positioned to allow X-rays 14 from the anode 7 to exit the housing. The anode 7 is a stationary anode, not a rotating anode; that is, the anode 7 is fixed in position and stationary relative to the housing 11. As described above, the anode 7 is solid, not a liquid anode (for comparison, some X-ray sources have liquid anodes designed so that the cathode emits a liquid jet of material during operation).
[0055] In some embodiments, the cathode 9 is a wound tungsten filament and the anode 7 contains copper. However, either or both of the anode 7 and cathode 9 may contain alternative materials. For example, the anode 7 may contain copper, chromium, cobalt-molybdenum, silver, gold, rhodium, iron, or tungsten.
[0056] In the embodiment shown in Figure 1, the focusing device 15 is located inside the housing 11 between the anode 7 and the cathode 9. The focusing device 15 is configured to influence the electric field inside the housing 11 to guide electrons emitted from the cathode 9 toward the anode 7, and further, to influence at least one of the shape and size of the region of the anode 7 irradiated with electrons. For example, as schematically shown in Figure 1, the focusing device may comprise multiple metal gratings. However, those skilled in the art will understand that a single metal grating may be used instead, or alternative focusing devices may be available. For example, the focusing device may be a magnetic focusing device that uses a magnetic field (such as a quadrupole magnetic field) to focus the X-rays. The voltage supplied to the grating may be changed to adjust the electric field inside the X-ray tube, and in particular to adjust the electric field near the electron beam irradiating the anode 7.
[0057] The X-ray source 3 further includes a control electronic circuit 17, which adjusts various operating parameters, including the operating voltage of the X-ray tube and the emission current of the X-ray tube (by adjusting the current supplied to the cathode and the operating voltage), and also adjusts the control parameters of the focusing device 15, such as the voltage applied to the focusing device 15.
[0058] In each embodiment, the X-ray analyzer is controlled to operate in at least two modes. In the first X-ray analysis mode, the effective focal spot size is less than 100 μm. Therefore, the X-ray source can be used for X-ray analysis applications that require a microfocus X-ray source. In the second X-ray analysis mode, the operating power of the X-ray tube is increased. Furthermore, the irradiated area of the anode is expanded (and therefore the area of the focal spot as seen from the measuring device that measures the X-ray beam emitted from the X-ray tube, i.e., the area of the effective focal spot, is also expanded). In this way, the X-ray tube is easy to use for a variety of X-ray analysis applications while reducing the risk of damage to the X-ray tube (especially the anode). For X-ray analysis applications that require a microfocus, the X-ray analyzer operates in the first X-ray analysis mode with an appropriate operating power setting. Furthermore, if a larger focal spot is required for a different X-ray analysis application, the X-ray analyzer operates in the second X-ray analysis mode. In other words, an X-ray analyzer can be operated in either a first mode, which focuses the beam onto a small point on the anode, or a second mode, which defocuses the beam onto a larger point on the anode.
[0059] The X-ray analyzer 1 includes an X-ray source 3 and a control device 5 that communicates with a control electronic circuit 17. The control device 5 includes a memory 19 that stores X-ray analysis mode information, an input unit 21 that receives X-ray analysis application information, and a processor 23 that selects the X-ray analysis mode of the X-ray tube according to the received X-ray analysis application information. The X-ray analysis mode information includes operating parameter values for at least two X-ray analysis modes. The control device 5 is configured to cause the control electronic circuit 17 to operate the X-ray tube according to the X-ray analysis mode selected by the control device 5.
[0060] In some embodiments, the aspect ratio of the effective focal spot is less than 1.5 in both the first and second X-ray analysis modes. For example, in the first X-ray analysis mode, the focal spot may be approximately circular, the effective focal spot may have a diameter of 20 μm, and the operating power of the X-ray tube may be 50 W or less. In the second X-ray analysis mode, the diameter of the effective focal spot may be 40 μm. Therefore, the area of the effective focal spot in the second X-ray analysis mode is significantly larger than in the first X-ray analysis mode. This makes it possible to increase the operating power in the second X-ray analysis mode without damaging the X-ray tube. In this way, X-ray analysis applications can adjust the operating power to match the size of the focal spot, making it easier to use focal spots of various sizes.
[0061] Similarly, the effective focus may be elongated. In the first X-ray analysis mode, the effective focus may have a maximum length / width of 20 μm, and the operating power of the X-ray tube may be 50 W or less. In the second X-ray analysis mode, the maximum length / width of the effective focus may be 40 μm. The area of the effective focus in the second X-ray analysis mode is significantly larger than that in the first X-ray analysis mode. This makes it possible to increase the operating power in the second X-ray analysis mode without damaging the X-ray tube. In this way, X-ray analysis applications can adjust the operating power according to the size of the focus, making it easier to use focuses of various sizes.
[0062] In some embodiments, the first X-ray analysis mode may have an effective focal spot with an aspect ratio (the ratio of the larger of the length and width to the other) close to 1 (i.e., between 1 and 1.5). However, in the second X-ray analysis mode, the effective focal spot may be elongated; that is, its effective focal spot may have an aspect ratio of 2.0 or greater. In this way, the X-ray analyzer can be used for both X-ray analysis applications that require a linear focal spot and X-ray analysis applications where a linear focal spot is undesirable or unsuitable.
[0063] In some embodiments, both the first X-ray analysis mode and the second X-ray analysis mode have elongated effective focal points. The aspect ratio of the effective focal point may be larger for the second X-ray analysis mode than for the first X-ray analysis mode.
[0064] The inventors recognized that by providing an X-ray source with a solid, fixed anode, along with a focusing device configured to affect the electron beam from the cathode, and a control device configured to control the focusing device according to the selected X-ray analysis mode, the X-ray source would last longer and become more economical and convenient. In particular, the X-ray source can be controlled to operate in multiple different X-ray analysis modes depending on the X-ray analysis being performed. In the first X-ray analysis mode, the effective focal size is less than 100 μm (i.e., the length, width, or diameter is less than 100 μm). Therefore, in the first X-ray analysis mode, the X-ray tube has a small focal spot, and the operating power is relatively low (compared to the second X-ray analysis mode) to protect the anode. In the second X-ray analysis mode, both the operating power of the X-ray tube and the irradiated area of the anode are increased. This allows the X-ray tube to be used in a variety of X-ray analysis applications with ease of use and minimal damage to the anode.
[0065] Table 1 below shows the operating parameters for two exemplary embodiments of the X-ray analysis mode, along with the dimensions of their respective effective focal points. The operating voltage is the high voltage applied across the anode.
[0066] TIFF0007897735000001.tif29170
[0067] As shown in Figure 1, the control device 5 is equipped with an input unit 21, which is an interface for receiving X-ray analysis application information. The user can input X-ray analysis application information such as identification information of the X-ray analysis to be performed, the type of sample to be analyzed, and the size of the sample to be analyzed, or information about the X-ray analyzer (for example, by specifying the optical elements used during the X-ray analysis) via the input unit 21.
[0068] The processor 23 is configured to determine the X-ray analysis mode in which the X-ray tube should operate based on the received X-ray analysis application information. Once an X-ray analysis mode is selected, the control unit 5 operates the X-ray source 3 in the selected mode. The input unit 21 may be configured to receive alphanumeric data. The input unit 21 may be configured to receive data via a wired connection through a user input device (e.g., a keyboard), or it may include a receiver for receiving data via a wireless connection, or both.
[0069] The X-ray analysis to be performed may refer to a specific type of measurement technique, such as two-dimensional small-angle X-ray scattering (2DSAXS), grazing incidence small-angle X-ray scattering (GISAXS), fine diffraction, computed tomography, residual stress analysis, texture analysis, Bragg-Brentano analysis, or any other type of X-ray analysis technique.
[0070] In some embodiments, the X-ray analyzer 1 may be equipped with interchangeable optical elements, and the control device 5 may be configured to select an X-ray analysis mode based on the interchangeable optical elements. An example of such an embodiment is illustrated with reference to Figure 2.
[0071] Figure 2 shows the X-ray analyzer 100. The X-ray analyzer 100 includes a first replaceable optical element 125.
[0072] The X-ray analyzer 100 is similar to the X-ray analyzer in Figure 1 and further comprises a sample stage 135 that supports the sample 130 to be analyzed. The X-ray analyzer 100 also comprises an X-ray detector 140 positioned to receive X-rays scattered (e.g., diffracted) by the sample 130. In some embodiments, the X-ray detector 140 may be an X-ray fluorescence detector and may be located in a different position than in Figure 2.
[0073] The X-ray source 103 is an X-ray tube comprising an anode 107 and a cathode 109 inside a sealed housing 111. The focusing device 115 is similarly located inside the housing 111, between the anode 107 and the cathode 109. The X-ray source includes control electronic circuits 117 that control various operating parameters, such as cathode current, voltage drop between the cathode and anode, and voltage applied to the focusing device 115. X-rays 114 from the anode 107 exit the housing 111 through a window 113. In Figure 2, the first replaceable optical element 125 is located in the path of the X-rays 114 from the X-ray tube. Thus, the first replaceable optical element 125 receives the X-rays directly from the X-ray tube. The X-rays pass through the first replaceable optical element 125 before irradiating the sample 130. The X-rays from the sample are received by the X-ray detector 140.
[0074] The first replaceable optical element 125 is not fixed to the housing 111. Since the first replaceable optical element 125 is removable from the X-ray analyzer, it can be replaced with a different optical element. In some embodiments, the replaceable optical element is replaced manually by an operator. Alternatively, the X-ray analyzer may have at least one actuator for removing and replacing the first replaceable optical element 125. In some embodiments, the replaceable optical element 125 is positioned to receive X-rays directly from the X-ray source. That is, X-rays from the X-ray source reach the first replaceable optical element 125 without passing through any intervening optical elements.
[0075] The first interchangeable optical element 125 is selected based on the X-ray analysis application to be performed. For example, the first interchangeable optical element 125 may include a two-dimensional focusing mirror, which is commonly used for two-dimensional (2D) small-angle X-ray scattering (2DSAXS), grazing-incident small-angle X-ray scattering (GISAXS), or fine diffraction. In some other embodiments, the first interchangeable optical element 125 may be a monocapillary collimator or a polycapillary collimator. These optical elements can be used to perform XRD stress analysis or XRD texture analysis. Alternatively, the first interchangeable optical element 125 may be a collimator slit, a one-dimensional mirror, or a hybrid monochromator (i.e., a combination of a multilayer mirror (X-ray mirror) bent along a parabolic curve and a channel-cut Ge crystal in a single module). These optical elements may be used in a variety of X-ray analysis applications, such as powder diffraction analysis.
[0076] The X-ray analyzer 100 may optionally include a further interchangeable optical element 127 ("second interchangeable optical element"). The second interchangeable optical element 127 may be any of the optical elements listed in the previous paragraph, as long as it is a different optical element from the first interchangeable optical element. For example, if the first interchangeable optical element 125 is a two-dimensional focusing mirror, the second interchangeable optical element 127 may be a monocapillary collimator, a polycapillary collimator, a collimator slit, or a hybrid collimator. The second interchangeable optical element 127 may be of the same type as the first interchangeable optical element 125, but may have a different structure. For example, both the first interchangeable optical element 125 and the second interchangeable optical element 127 may be collimator slits, and these two slits may have different dimensions from each other. As indicated by the rotating arrow, the first interchangeable optical element 125 is replaceable (or interchangeable) with the second interchangeable optical element 127, and vice versa.
[0077] The X-ray analyzer 100 further comprises a control device 105. The control device 105 includes a memory 119, which stores information defining multiple X-ray analysis modes. Each X-ray analysis mode can specify the operating power of the X-ray tube, as well as the size or area of the effective focal spot, or both. These multiple different X-ray analysis modes may be optimized for multiple different X-ray analysis applications or multiple different optical elements, or both.
[0078] In some embodiments, the X-ray analysis mode may be selected based on the type of interchangeable optical element used in the X-ray analysis application. The control unit may store a single X-ray analysis mode corresponding to that optical element; that is, there may be a one-to-one correspondence between optical elements and X-ray analysis modes. Alternatively, the control unit may store multiple analysis modes for each optical element. In this case, the control unit may be configured to select a subset of X-ray analysis modes corresponding to the optical element.
[0079] In Figure 2, the first replaceable optical element 125 is positioned in the path of the incident X-ray beam. The control unit 105 receives X-ray analysis information, including information identifying the first replaceable optical element 125. This information may be input by the user or received from a sensor (not shown) configured to detect, identify, or both the first replaceable optical element 125. The processor 123 processes the information identifying the first replaceable optical element 125 and selects an appropriate X-ray analysis mode. In this way, the control unit 105 can select an X-ray analysis mode optimized for the X-ray analysis optical element being used. If there is a one-to-one correspondence between the optical element and the X-ray analysis mode, once an appropriate X-ray analysis mode is selected, the control unit communicates with the X-ray source to control the X-ray source to operate according to the selected X-ray analysis mode. If the optical element supports multiple X-ray analysis modes, the control unit selects a subset of the X-ray analysis modes corresponding to the optical element. The user may select an X-ray analysis mode from a subset, and the control device 105 controls the X-ray source 103 to operate according to that mode.
[0080] In some embodiments, the control device 105 may be configured to select an X-ray analysis mode based on information other than information that identifies the type of optical element used.
[0081] In some embodiments, the control device 105 may be configured to select an X-ray analysis mode based on information about the sample, such as the size and material of the sample. Alternatively, the control device may select an X-ray analysis mode based on information that identifies the type of X-ray analysis application to be performed.
[0082] For example, the X-ray analysis information may include information specifying whether the X-ray analysis to be performed requires high resolution or low resolution. Based on this information, the control device may select an appropriate X-ray analysis mode. The control device 105 may be configured to operate the X-ray source 103 in either a first X-ray analysis mode, which is a low-resolution mode, or a second X-ray analysis mode, which is a high-resolution mode. The aspect ratio of the effective focal spot in high-resolution mode may be larger than that in low-resolution mode. The control device may decide whether to operate in high-resolution mode or low-resolution mode based on information specifying the type of sample, or based on information specifying the type of measurement to be performed. In these embodiments, the X-ray analyzer may have only one interchangeable optical element, such as a hybrid monochromator (i.e., in Figure 2, the X-ray analyzer has a first interchangeable optical element 125, but a second interchangeable optical element 127 may not be present).
[0083] Figure 3 shows the shape of the effective focal point in some examples of various X-ray analysis modes.
[0084] In Figure 3A, the effective focus is approximately circular. Therefore, the ratio of the length of the effective focus to the width of the effective focus (i.e., the aspect ratio of the focus) is approximately 1. In some examples, the width and length of the focus may be 20 μm. In these examples, according to the measurement method described in this specification, the size of the effective focus is 20 μm, and the area of the effective focus is 400 μm. 2 That is the case.
[0085] The effective focus in Figure 3B is similar in shape to that in Figure 3A, but larger. In some examples, the maximum dimension may be 45 μm, and the aspect ratio may be approximately 1. Therefore, the size of the effective focus is 45 μm, and the area of the effective focus is 2025 μm. 2 That is the case.
[0086] In Figure 3C, the effective focus is elongated. In some examples, the focal length may be approximately 100 μm, and the focal width may be approximately 40 μm. Therefore, the size of the effective focus is 100 μm.
[0087] In Figure 3D, the effective focus is elongated. In some examples, the focal length may be approximately 400 μm and the focal width approximately 60 μm. Therefore, the size of the effective focus is 400 μm. It will be understood that these are merely examples showing the size and area of the effective focus. These dimensions can be made smaller or larger.
[0088] Figure 4 shows an X-ray analysis method according to one embodiment of the present invention. In the first step 201, the control unit receives X-ray analysis information. This X-ray analysis information may be any or a combination of information identifying interchangeable optical elements, information about the sample to be analyzed, and information identifying the type of X-ray analysis measurement to be performed (i.e., X-ray analysis application). In the next step 203, the control unit selects the X-ray analysis mode of the X-ray source based on the received X-ray analysis information. In the next step 205, the control unit communicates with the X-ray source to control at least one of the operating voltage and filament current of the X-ray tube, thereby controlling the operating power of the X-ray tube. Furthermore, the control unit communicates with the X-ray source to control the voltage of the focusing device (e.g., lattice voltage), thereby controlling the size of the focal spot.
[0089] In some embodiments, step 201, which involves inputting X-ray analysis application information, may include inputting information via the control unit to identify interchangeable optical elements used in the X-ray analyzer and executing the X-ray analysis application. Furthermore, step 203, which involves selecting an X-ray analysis mode, may include identifying an X-ray analysis mode corresponding to the interchangeable optical elements identified in the previous step. The control unit may store a database of X-ray analysis modes. Identifying an X-ray analysis mode corresponding to an interchangeable optical element may involve identifying multiple X-ray analysis modes that belong to one subset of X-ray analysis modes in the database. Alternatively, there may be a one-to-one correspondence between X-ray analysis modes and optical elements, in which case identifying an X-ray analysis mode involves selecting a single X-ray analysis mode corresponding to the identified optical element.
[0090] In some embodiments, step 201, which involves inputting X-ray analysis application information, may include inputting information that identifies the sample via the control device of the X-ray analyzer. Step 203, which involves selecting the X-ray analysis mode, may include identifying the X-ray analysis mode corresponding to the sample identified in the previous step. For example, the sample may correspond to a specific optical element, and the X-ray analyzer may examine the sample using that optical element using both high-resolution and low-resolution X-ray analysis modes. The user may select between high-resolution and low-resolution modes, thereby causing the control device to operate the X-ray analyzer according to the selected mode.
[0091] In some embodiments, step 201, which involves inputting X-ray analysis application information, may include inputting information that identifies the X-ray analysis application to be executed via the control device of the X-ray analyzer. The control device may store a database of X-ray analysis modes. An X-ray analysis application may correspond to one or more X-ray analysis modes. Step 203, which involves selecting an X-ray analysis mode, may include identifying an X-ray analysis mode that corresponds to the X-ray analysis application identified in the previous step. Identifying an X-ray analysis mode may include identifying multiple X-ray analysis modes that belong to one subset of X-ray analysis modes in the database. Alternatively, there may be a one-to-one correspondence between X-ray analysis modes and optical elements, in which case identifying an X-ray analysis mode includes selecting a single X-ray analysis mode that corresponds to the identified optical element.
[0092] Figure 1 shows an X-ray analyzer with a focusing device equipped with multiple gratings, but it will be understood that alternative focusing devices can also be used. For example, the focusing device may be a magnetic focusing device. A magnetic focusing device can focus using a magnetic field. As an example, the focusing device may use a quadrupole magnetic field to achieve focusing.
[0093] Furthermore, the focusing device does not necessarily have to be located inside or outside the housing.
[0094] If the focusing device has at least one focusing grating, there may be more or fewer gratings than two. The X-ray source may have a single grating or multiple gratings. Any number of gratings can be used.
[0095] Generally, the term "X-ray tube" is understood to refer to an X-ray source having a sealed housing in which the cathode and anode are located. The housing may or may not be roughly tubular in shape.
[0096] In some embodiments, the cathode may be a coiled wire filament. In other embodiments, the cathode may comprise a metal loop. The cathode may or may not contain tungsten.
[0097] Figure 2 shows an X-ray detector that receives X-rays that have been diffracted, scattered, or both by the sample. However, it will be understood that the X-ray detector could also be an X-ray detector that receives fluorescence emitted from the sample. In these embodiments, the X-ray detector may be positioned directly above the sample or at an alternative location.
[0098] In some embodiments, the X-ray analyzer may include both an XRF detector and an XRD detector.
[0099] The apparatus in Figure 2 may or may not include a second replaceable optical element. Determination of the size and area of the effective focal point
[0100] The effective focal size is the larger of the focal length and width, as viewed from the measuring device.
[0101] The effective focal length can be determined by indirect measurement using geometric blur measurement.
[0102] This test method involves imaging the sharp edges of the object being tested. An X-ray image of a highly attenuating object is acquired, and the intensity profile of this image is used to determine the size of the effective focal spot.
[0103] Referring to Figure 5, the object under test is positioned between the output window (not shown) of the X-ray tube and the detector 305 so as to be irradiated by X-rays emitted from the anode 303. The operating voltage of the X-ray tube may depend on the operating power of the X-ray tube, but in any case it is less than 225 kV. The object under test 301 is a spherical ball made of tungsten with a diameter of 0.9 mm. This ball is placed on a polyethylene support at a distance of at least 4.5 cm from the focal point on the anode. The distance between the object under test 301 and the detector 305 allows for projection magnifications between 20x and 100x. This magnification is adjusted to optimize image clarity (a larger magnification may be required for a relatively small focal point). The projection magnification is the ratio of the distance from the anode of the X-ray tube to the detector to the distance from the anode of the X-ray tube to the object under test.
[0104] An image of the object under inspection is captured by the detector, and an image processor is used to form a linear intensity profile in the length direction and a linear intensity profile in the width direction. More specifically, these linear intensity profiles are acquired along the center of the image in the length and width directions (in the central length direction and in the central width direction).
[0105] The line scan of an image in the central length direction is the intensity profile of the X-ray image along the center of the image, parallel to the longitudinal axis of the X-ray tube. If the longitudinal axis of the X-ray tube is not specified, the central length direction is parallel to the electron orbits. The width direction is perpendicular to the length direction.
[0106] Subsequently, the image processor determines the diameter of the object under inspection when the total contrast of the image reaches 50% by measuring the distance between two related points on the line. For example, in Figure 6, which shows a line scan in the longitudinal direction, the diameter in the longitudinal direction (D l ) is the distance between point B and point C.
[0107] Next, at a contrast of 90%, two more points (points A and D in Figure 6) are acquired. Then, the focal sizes l and w are calculated using equations (1) and (2).
number
number
number
number
number
[0108] Those skilled in the art will understand that the term "spot" in "focal spot" does not necessarily refer to a circle, but can refer to any two-dimensional shape. In this specification, the area of the effective focal spot is the product of the measured length and the measured width (regardless of the shape of the focal spot).
Claims
1. An X-ray analyzer that performs multiple X-ray analysis applications to analyze a sample by measuring at least one of X-ray diffraction and X-ray fluorescence, The aforementioned X-ray analyzer, An X-ray source for irradiating the aforementioned sample with X-rays, comprising a solid anode and a cathode that emits an electron beam, A focusing device for focusing the electron beam onto the anode, A control device, It is configured to receive X-ray analysis application information, and, Based on the aforementioned X-ray analysis application information, the X-ray analyzer is configured to be controlled in order to selectively operate in either the first X-ray analysis mode or the second X-ray analysis mode. Control device and Equipped with, In the first X-ray analysis mode, the X-ray source is It is controlled to operate with a first operating power and a first operating voltage, and The effective focal size is less than 100 μm. In the second X-ray analysis mode, the X-ray source is It is controlled to operate with a second operating power and a second operating voltage. The second operating power is greater than the first operating power. The area of the effective focal spot is larger than the area of the effective focal spot in the first X-ray analysis mode. X-ray analyzer.
2. An X-ray analyzer according to claim 1, The aforementioned X-ray source is, In the first X-ray analysis mode, the effective focal spot size is less than 55 μm. In the second X-ray analysis mode, the size of the effective focal spot is greater than 60 μm. X-ray analyzer.
3. An X-ray analyzer according to claim 1 or claim 2, The X-ray analyzer further comprises a first replaceable X-ray optical element arranged to receive X-rays from the X-ray source. X-ray analyzer.
4. An X-ray analyzer according to claim 3, The control device is configured to receive information identifying the first replaceable X-ray optical element, and The control device is configured to operate the X-ray analyzer in either the first X-ray analysis mode or the second X-ray analysis mode based on the information identifying the first replaceable X-ray optical element. X-ray analyzer.
5. An X-ray analyzer according to claim 1 or 2, The effective focus has an aspect ratio greater than 2.0 in both the first X-ray analysis mode and the second X-ray analysis mode. The control device is It is configured to receive sample information, and, Based on the sample information, the X-ray analyzer is configured to operate in either the first X-ray analysis mode or the second X-ray analysis mode. X-ray analyzer.
6. An X-ray analyzer according to claim 1 or 2, In the first X-ray analysis mode, The size of the effective focal spot is less than 40 μm. The aspect ratio of the effective focus is less than 1.
5. The first operating power is less than 50W. X-ray analyzer.
7. An X-ray analyzer according to claim 1 or 2, In the second X-ray analysis mode, The size of the effective focal spot is larger than that of the first X-ray analysis mode, and is greater than 60 μm. The aspect ratio of the effective focus is less than 1.
5. The second operating power is over 50W. X-ray analyzer.
8. An X-ray analyzer according to claim 1 or 2, In the first X-ray analysis mode, the effective focal spot has an aspect ratio of less than 1.
5. In the second X-ray analysis mode, the effective focal spot is elongated and has an aspect ratio greater than 2.
0. X-ray analyzer.
9. An X-ray analyzer according to claim 8, In the second X-ray analysis mode, The size of the effective focal spot is greater than 60 μm. The second operating power is over 50W. X-ray analyzer.
10. An X-ray analyzer according to claim 1 or 2, The size of the effective focal spot in the second X-ray analysis mode is greater than 100 μm. The second operating power is 100W or more. X-ray analyzer.
11. An X-ray analyzer according to claim 1 or 2, A sample stage for supporting the sample, wherein the X-ray source is arranged to irradiate the sample with X-rays directed along the incident beam path, A detector arranged to receive X-rays scattered by or emitted from the sample, It also has, X-ray analyzer.
12. An X-ray analyzer according to claim 11, The X-ray analyzer comprises a first replaceable X-ray optical element, The X-ray analyzer further comprises a first actuator, The first actuator is configured to move the first replaceable X-ray optical element between an in-beam position and an out-beam position. The beam position is the position when the first replaceable X-ray optical element is located within the incident beam path. The aforementioned off-beam position is the position when the first replaceable X-ray optical element is located outside the incident beam path. The control device is It is configured to receive information that identifies the position of the first replaceable X-ray optical element, and The X-ray analyzer is configured to operate in either the first X-ray analysis mode or the second X-ray analysis mode based on the position of the first replaceable X-ray optical element. X-ray analyzer.
13. A method for controlling an X-ray analyzer according to claim 1, The steps include: the control unit receiving X-ray analysis application information, Based on the aforementioned X-ray analysis application information, the step of selecting either a first X-ray analysis mode or a second X-ray analysis mode, The steps include controlling the X-ray source to operate in the selected mode, Includes, In the first X-ray analysis mode, the X-ray source is It is controlled to operate with a first operating power, and The effective focal size is less than 100 μm. In the second X-ray analysis mode, the X-ray source is It is controlled to operate at a second operating power higher than the first operating power, The area of the effective focal spot is larger than the area of the effective focal spot in the first X-ray analysis mode. method.
14. The method according to claim 13, The aforementioned X-ray source is, In the first X-ray analysis mode, the effective focal spot size is less than 55 μm. In the second X-ray analysis mode, the size of the effective focal spot is greater than 60 μm. method.
15. A computer program product comprising a tangible, non-temporary computer-readable medium that stores multiple program instructions, The aforementioned multiple program instructions are The X-ray analyzer according to claim 1 or 2, To perform the steps of the method according to claim 13 or 14, Computer program products.