X-ray analysis apparatus and method with hybrid control of beam divergence

Abstract

This application relates to an X-ray analysis apparatus and method having a hybrid control of the beam divergence. The apparatus includes an adjustable slit (210, 210a) located between an X-ray source (4) and a sample (6); and optionally another slit (220). A controller (17) is configured to control the width of the adjustable slit between a first width, a larger second width, and an even larger third width. At the first width and the second width: the adjustable slit (210) limits the divergence of the incident beam, thereby limiting the irradiated area of the sample; and the other slit (220) does not limit the divergence of the incident beam. At the third width: the adjustable slit (210) does not limit the divergence of the incident beam, and the other slit (220) limits the divergence of the incident beam, thereby limiting the irradiated area of the sample. Alternatively, at the third width, the adjustable slit (210) continues to limit the irradiated area.

Description

Field of the Invention

[0001] The present invention relates to devices and methods for X-ray analysis. Embodiments particularly relate to X-ray diffraction devices and methods for performing X-ray diffraction measurements. Background

[0002] X-ray diffraction is an analytical technique for characterizing material samples. A specific method of X-ray diffraction is the Bragg Brentano method. Other methods of analyzing substances using X-rays include Grazing Incidence X-ray Diffraction (GIXRD), Small Angle X-ray Scattering (SAXS), Grazing Incidence Small Angle X-ray Scattering (GISAXS), X-ray microdiffraction, and X-ray Reflectometry. Other types of X-ray analysis include X-ray fluorescence.

[0003] Generally, X-ray measurements are performed by directing X-rays from an X-ray source along the incident beam path onto a sample and detecting the X-rays from the sample using an X-ray detector.

[0004] X-ray optics such as divergence slits, anti-scatter slits, and collimators can be provided on the incident and / or diffracted / scattered beam side. The X-ray optics are selected according to the specific method used.

[0005] In addition, X-ray measurements are typically performed on a batch of samples. To optimize the quality of the results, the X-ray optics can be specifically selected for the type of sample to be analyzed.

[0006] To use X-ray analysis equipment for different applications, the user must reconfigure the X-ray equipment. This requires expertise. In addition, reconfiguring the X-ray equipment is neither convenient nor time-efficient.

[0007] Accordingly, there is a desire to provide an X-ray device that can achieve high-quality measurements for multiple different applications with minimal manual reconfiguration.

[0008] In the past, fixed divergence slits have been used in some applications. This creates an irradiated area on the sample, the size of which decreases as the incident beam angle increases.

[0009] In some other applications, a programmable (adjustable) divergent slit is used. This can allow the control of the beam divergence according to the incident beam angle, such that when the incident beam angle changes, a constant, fixed area of the sample is illuminated. An anti-scatter slit is typically used behind the adjustable divergent slit (i.e., between the adjustable slit and the sample) because the adjustable slit may produce parasitic scatter. However, this anti-scatter slit does not limit the divergence of the incident beam. In other words, it does not block or interfere with the beam itself; it only blocks scattered light.

[0010] Overview

[0011] The present invention is defined by the claims. According to one aspect of the present invention, an X-ray analysis apparatus is provided, comprising:

[0012] an X-ray source configured to generate X-rays;

[0013] a sample stage configured to support a sample, the X-ray source and the sample stage being arranged such that the X-rays generated by the X-ray source define an incident beam irradiating the sample;

[0014] an adjustable slit between the X-ray source and the sample;

[0015] another slit between the X-ray source and the adjustable slit, or between the adjustable slit and the sample; and

[0016] a controller configured to control the width of the adjustable slit,

[0017] wherein the controller is configured to change the width of the adjustable slit between a first width, a second width, and a third width, the third width being greater than the second width, and the second width being greater than the first width, wherein

[0018] at the first width:

[0019] the adjustable slit limits the divergence of the incident beam to a first divergence angle, thereby limiting the irradiated area of the sample; and

[0020] the another slit preferably does not limit the divergence of the incident beam,

[0021] at the second width:

[0022] the adjustable slit limits the divergence of the incident beam to a second divergence angle, thereby limiting the irradiated area of the sample; and

[0023] the another slit preferably does not limit the divergence of the incident beam, and

[0024] at the third width:

[0025] the adjustable slit does not limit the divergence of the incident beam, and

[0026] Another slit limits the divergence of the incident light beam to a third divergence angle, thereby limiting the irradiated area of the sample.

[0027] Wherein, the third divergence angle is greater than the second divergence angle, and the second divergence angle is greater than the first divergence angle.

[0028] The present inventors have recognized that a hybrid system would be advantageous, in which in some configurations an adjustable slit limits the divergence of the incident light beam, and in some other configurations another slit limits the divergence of the incident light beam.

[0029] If the other slit is located between the adjustable slit and the sample, then, when the adjustable slit limits the divergence of the incident light beam, the other slit can be used as an anti-scattering slit without blocking or disturbing the incident light beam itself.

[0030] Conversely, if the other slit is located between the X-ray source and the adjustable slit, the adjustable slit can be used as an anti-scattering slit for the X-rays scattered by the other slit. In particular, when the other slit limits the divergence of the incident light beam, the adjustable slit can be used as an anti-scattering slit.

[0031] The incident light beam passes through the adjustable slit and the other slit.

[0032] When set to a first width and a second width, the adjustable slit blocks a portion of the incident light beam.

[0033] When set to a third width, the adjustable slit is preferably outside the incident light beam. That is, at the third width, the adjustable slit preferably does not block or disturb any portion of the incident light beam.

[0034] The adjustable slit can be used as a programmable divergence slit. If the other slit is located between the adjustable slit and the sample, then, when the adjustable slit is set to the first width and the second width, the other slit can be used as an anti-scattering slit. When the adjustable slit is set to the third width, the other slit can be used as a divergence slit.

[0035] The apparatus generally further includes an X-ray detector, which is arranged to receive X-rays from the sample. In various different cases, these X-rays may be diffracted X-rays, scattered X-rays, or X-rays generated by fluorescence in the sample.

[0036] In some embodiments, the other slit is a non-adjustable slit.

[0037] If the non-adjustable other slit is located between the adjustable slit and the sample, then, when the adjustable slit is set to the first width and the second width, the non-adjustable other slit can be used as a fixed anti-scattering slit. When the adjustable slit is set to the third width, the non-adjustable other slit can be used as a fixed divergence slit.

[0038] Since the non-adjustable slit does not need to be clear of the beam in all configurations of the adjustable slit, the non-adjustable slit can have a narrower width than previous instances combining a programmable diverging slit and a scatter guard slit. This narrower width can allow for improved suppression of scattering when the adjustable slit controls the beam divergence.

[0039] If another non-adjustable slit is located between the X-ray source and the adjustable slit, then the adjustable slit can be used as an adjustable scatter guard slit when it is set to a third width.

[0040] In other embodiments, the another slit can be an adjustable slit.

[0041] The X-ray analysis device may further include a goniometer, wherein the X-ray source is mounted to the goniometer to irradiate the sample at different incident angles within a range. In some embodiments, the X-ray source can be rotatable about the axis of the goniometer. Optionally or additionally, the sample stage can be rotated so that the sample is irradiated at different incident angles within the range.

[0042] The controller can be configured to control the goniometer and the adjustable slit such that: when the goniometer is set to a first incident angle, the adjustable slit is set to a first width; when the goniometer is set to a second incident angle, the adjustable slit is set to a second width; and when the goniometer is set to a third incident angle, the adjustable slit is set to a third width, the third incident angle being greater than the second incident angle, and the second incident angle being greater than the first incident angle.

[0043] Thus, the third angle is the highest incident angle, and the first angle is the lowest incident angle. The second angle is between the first angle and the third angle.

[0044] The controller can be configured to control the width of the adjustable slit such that, within the range of the incident angles of the goniometer, the incident beam irradiates a constant area of the sample.

[0045] In particular, the controller can control the width of the adjustable slit such that the incident beam irradiates a constant area of the sample at the first angle and the second angle.

[0046] In this way, the device can operate in a first mode at low angles and in a second mode at high angles. In the first mode, by controlling the width of the adjustable slit according to the angle of the goniometer, the incident beam illuminates a fixed length of the sample (i.e., irradiates a constant area). In the second mode, the incident beam has a fixed divergence controlled by another slit.

[0047] In the first mode, the controller controls the adjustable slit to open wider as the angle of the incident beam increases.

[0048] The apparatus can operate alternately in two different modes for two different types of measurements.

[0049] The X-ray analysis apparatus may further include an X-ray detector that is arranged to receive X-rays from a sample and is configured to generate an output signal that measures the intensity of the received X-rays. The controller is optionally configured to receive the output signal from the X-ray detector and is configured to normalize the measured intensity by: when the adjustable slit is set to a first width or a second width, performing a first normalization calculation based on the width of the adjustable slit; and when the adjustable slit is set to a third width, performing a second normalization calculation based on the width of another slit.

[0050] In this way, the controller can automatically correct the influence of different slits on the intensity of the detected X-rays.

[0051] In some embodiments, the X-ray analysis apparatus may be configured for X-ray fluorescence measurement.

[0052] In some embodiments, the X-ray analysis apparatus may be a diffractometer.

[0053] The apparatus is preferably configured for powder diffraction measurement (diffractometry).

[0054] According to another aspect of the present invention, there is provided a method for X-ray analysis using an apparatus, the apparatus including:

[0055] An X-ray source configured to generate X-rays;

[0056] A sample stage configured to support a sample, the X-ray source and the sample stage being arranged such that the X-rays generated by the X-ray source define an incident beam that irradiates the sample;

[0057] An adjustable slit between the X-ray source and the sample;

[0058] Another slit between the X-ray source and the adjustable slit, or between the adjustable slit and the sample; and

[0059] A controller configured to control the width of the adjustable slit,

[0060] The method includes:

[0061] Setting the adjustable slit to a first width by the controller, at which first width the adjustable slit limits the divergence of the incident beam to a first divergence angle, thereby limiting the irradiated area of the sample, and the other slit preferably does not limit the divergence of the incident beam;

[0062] The adjustable slit is set to a second width by a controller, at which the adjustable slit limits the divergence of the incident beam to a second divergence angle, thereby limiting the irradiated area of the sample, and the other slit preferably does not limit the divergence of the incident beam; and

[0063] The adjustable slit is set to a third width by a controller, at which the adjustable slit does not limit the divergence of the incident beam, and the other slit limits the divergence of the incident beam to a third divergence angle, thereby limiting the irradiated area of the sample,

[0064] wherein the third width is greater than the second width, and the second width is greater than the first width, and

[0065] wherein the third divergence angle is greater than the second divergence angle, and the second divergence angle is greater than the first divergence angle.

[0066] The other slit may be a non-adjustable slit.

[0067] Optionally, when the incident beam irradiates the sample at a first incident angle, the controller sets the adjustable slit to a first width; when the incident beam irradiates the sample at a second incident angle, the controller sets the adjustable slit to a second width; and when the incident beam irradiates the sample at a third incident angle, the controller sets the adjustable slit to a third width, wherein the third incident angle is greater than the second incident angle, and the second incident angle is greater than the first incident angle.

[0068] The controller can control the width of the adjustable slit such that within the range of incident angles, the incident beam irradiates a constant area of the sample.

[0069] The method may further include: detecting X-rays in the secondary beam scattered, diffracted or emitted by the sample; measuring the intensity of the X-rays in the secondary beam; and normalizing the measured intensity to produce a normalized intensity, including: performing a first normalization calculation based on the width of the adjustable slit when the adjustable slit is set to the first width or the second width; and performing a second normalization calculation based on the width of the other slit when the adjustable slit is set to the third width.

[0070] According to another aspect of the present invention, a method for X-ray analysis using a device is provided, the device including:

[0071] An X-ray source configured to generate X-rays;

[0072] A sample stage configured to support a sample, the X-ray source and the sample stage being arranged such that the X-rays generated by the X-ray source define an incident beam irradiating the sample;

[0073] An adjustable slit between the X-ray source and the sample;

[0074] A goniometer, wherein an X-ray source is mounted to the goniometer so as to be rotatable about an axis of the goniometer, thereby irradiating a sample at different incident angles within a range; and

[0075] A controller configured to control the goniometer and the width of an adjustable slit,

[0076] The method includes:

[0077] When the goniometer is set to a first incident angle, the adjustable slit is set to a first width by the controller, at which width the adjustable slit limits the divergence of the incident light beam to a first divergence angle, thereby limiting the irradiated area of the sample;

[0078] When the goniometer is set to a second incident angle, the adjustable slit is set to a second width by the controller, at which width the adjustable slit limits the divergence of the incident light beam to a second divergence angle, thereby limiting the irradiated area of the sample;

[0079] When the goniometer is set to a third incident angle, the adjustable slit is set to a third width by the controller, at which width the adjustable slit limits the divergence of the incident light beam to a third divergence angle, thereby limiting the irradiated area of the sample; and

[0080] When the goniometer is set to a fourth incident angle, the adjustable slit is set to the third width by the controller,

[0081] wherein the third width is greater than the second width, and the second width is greater than the first width,

[0082] wherein the third divergence angle is greater than the second divergence angle, and the second divergence angle is greater than the first divergence angle, and

[0083] wherein the fourth incident angle is greater than the third incident angle, the third incident angle is greater than the second incident angle, and the second incident angle is greater than the first incident angle.

[0084] According to this aspect, the adjustable slit is adjusted to the first width and a different second width at the first incident angle and the second incident angle, respectively. At the third incident angle and the fourth incident angle, the width of the adjustable slit is fixed at the third width. In this way, the adjustable slit can perform the functions of both a fixed slit and an adjustable slit. In some embodiments, this can reduce the need for another slit. At the third incident angle and the fourth incident angle, the adjustable slit is controlled to limit the divergence of the incident light beam to a fixed divergence angle, i.e., the third divergence angle.

[0085] The controller can control the width of the adjustable slit such that the incident light beam irradiates a constant area of the sample within a range of incident angles from the first incident angle to the second incident angle.

[0086] In this way, the adjustable slit is controlled to provide a constant illumination area on the sample at low incident angles and a constant divergence at higher incident angles.

[0087] The apparatus optionally includes another slit. The another slit can be a non-adjustable slit.

[0088] The another slit can be located between the adjustable slit and the sample such that the incident beam passes through the another slit, but the another slit does not limit the divergence of the incident beam.

[0089] The another slit is preferably used as an anti-scattering slit. In particular, it can be configured to block the scattering generated by the adjustable slit.

[0090] There is also provided a computer program including computer program code, which is configured to cause a controller of an X-ray analysis apparatus to perform all steps in the method outlined above when the computer program is run on the controller. The computer program can be included on a non-transitory computer-readable medium.

[0091] According to a further aspect of the present invention, there is provided an X-ray analysis apparatus, comprising:

[0092] An X-ray source configured to generate X-rays;

[0093] A sample stage configured to support a sample, the X-ray source and the sample stage being arranged such that the X-rays generated by the X-ray source define an incident beam for irradiating the sample;

[0094] An adjustable slit between the X-ray source and the sample;

[0095] A goniometer, wherein the X-ray source is mounted to the goniometer so as to irradiate the sample at different incident angles within a range; and

[0096] A controller configured to control the goniometer and the width of the adjustable slit,

[0097] wherein the controller is configured to change the width of the adjustable slit between a first width, a second width, and a third width, the third width being greater than the second width, and the second width being greater than the first width, wherein

[0098] At the first width:

[0099] The adjustable slit limits the divergence of the incident beam to a first divergence angle, thereby limiting the irradiated area of the sample,

[0100] At the second width:

[0101] The adjustable slit limits the divergence of the incident beam to a second divergence angle, thereby limiting the irradiated area of the sample, and

[0102] At the third width:

[0103] The adjustable slit limits the divergence of the incident light beam to a third divergence angle, thereby limiting the irradiated area of the sample.

[0104] Wherein, the third divergence angle is greater than the second divergence angle, and the second divergence angle is greater than the first divergence angle.

[0105] Wherein, the controller is configured to control the goniometer and the adjustable slit such that:

[0106] When the goniometer is set to the first incident angle, the adjustable slit is set to the first width;

[0107] When the goniometer is set to the second incident angle, the adjustable slit is set to the second width;

[0108] When the goniometer is set to the third incident angle, the adjustable slit is set to the third width; and

[0109] When the goniometer is set to the fourth incident angle, the adjustable slit is set to the third width.

[0110] The fourth incident angle is greater than the third incident angle, the third incident angle is greater than the second incident angle, and the second incident angle is greater than the first incident angle.

[0111] The X-ray analysis device may further include an X-ray detector, which is arranged to receive X-rays from the sample and is configured to generate an output signal for measuring the intensity of the received X-rays. Optionally, the controller is configured to receive the output signal from the X-ray detector and is configured to normalize the measured intensity by performing a normalization calculation based on the width of the adjustable slit when the adjustable slit is set to the first width, the second width, or the third width. BRIEF DESCRIPTION OF THE DRAWINGS

[0112] Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0113] Figure 1 is a schematic cross-sectional side view of an X-ray diffraction device according to an embodiment of the present invention;

[0114] Figure 2 shows Figure 1 a simplified schematic diagram of the beam formation in the X-ray diffraction device of

[0115] Figure 3 shows Figure 1 a simplified schematic diagram of the beam formation in the X-ray diffraction device of

[0116] Figure 4 shows Figure 1 a simplified schematic view of the formation of a light beam in an X-ray diffractometer, where a programmable divergence slit is set to a third width;

[0117] Figure 5 shows the process of irradiating a constant area of a sample with an incident light beam by combining an incident angle to change the light beam divergence;

[0118] Figure 6 is a flowchart of a method for performing X-ray measurement according to an embodiment of the present invention;

[0119] Figure 6A is as Figure 6 a flowchart of a method that is a variant of the method shown; and

[0120] Figure 7 is according to Figure 1 a schematic view of an X-ray diffractometer according to an alternative embodiment.

[0121] It should be noted that these figures are schematic and not drawn to scale. For clarity and convenience in the drawings, the relative sizes and proportions of the components of these figures are enlarged or reduced in size. Detailed description

[0122] Figure 1 shows a schematic view of an X-ray diffractometer according to an exemplary embodiment of the present invention.

[0123] Refer to Figure 1 , the X-ray device 2 includes an X-ray source (X-ray tube 4), which is arranged to generate X-rays and direct them towards a sample 6 supported by a sample stage 8. A flat graded multilayer 10 is provided on the path of the X-ray beam 12 between the X-ray tube 4 and the sample stage 8. As described in EP 2896960, by providing a flat graded multilayer, the X-ray device can be used for Bragg-Brentano and SAXS measurements.

[0124] The X-ray tube 4 has a line focus, which produces a divergent X-ray beam 12 that is incident on the flat-type gradient multilayer structure and ultimately on the sample 6. The sample 6 diffracts the incident X-ray beam 12. The X-ray detector 14 with an X-ray detection area 15 is arranged to detect the X-rays from the sample, which are diffracted along the diffracted X-ray beam path towards the X-ray detection area 15. The X-ray detector 14 and the X-ray tube are mounted on a goniometer (not shown). The angle θ of the incident X-ray beam is changed by rotating the X-ray tube about an axis. The X-ray detector is rotated about the same axis to detect the X-rays diffracted by the sample at an angle of 2θ relative to the incident X-ray beam. A first support member 16 for one or more collimators is provided between the sample stage 8 and the X-ray detector 14. The X-ray detector can be operated in 2D mode, 1D mode, or 0D mode by selecting how to read out the active area of the detection area 15. For Bragg-Brentano measurements, 1D mode is used.

[0125] The X-ray apparatus further includes a controller 17 for controlling the position and configuration of various components. The controller 17 communicates with a first actuator 21. The first actuator 21 is arranged to change the position of the first support member 16 to move one or more collimators.

[0126] In Figure 1 the illustrated embodiment, the first support member 16 supports a first collimator 18 and a second collimator (not shown). The first collimator 18 allows a beam having an angular divergence within a first angular range to pass through it. The angular divergence of the second collimator is greater than that of the first collimator 18, so that a wider beam can pass through it.

[0127] By providing an arrangement in which the controller 17 moves the first support member 16 between a first configuration and a second configuration, the X-ray apparatus can be reconfigured in a convenient manner. By moving the first support member 16 between the first configuration and the second configuration, the first collimator 18 is replaced by the second collimator. In addition, by providing an arrangement in which the first support member 16 is arranged to move axially, the configuration of the first support member can be changed without interfering with the angular range 2θ of the detector.

[0128] At the same time, by providing an arrangement in which the first support member 16 is arranged to move transversely (axial direction) through the beam path relative to the X-ray detector 14, a compact arrangement is provided.

[0129] A programmable anti-scatter slit 11 is provided in the secondary X-ray beam path from the sample 6 to the detection area 15 of the detector 14. The controller 17 is configured to control the size of the opening of the programmable anti-scatter slit such that the size of the slit can be changed according to the type of measurement being performed.

[0130] The beam mask component 22 is disposed on the incident beam side. In this embodiment, the beam mask component includes a first mask wheel. In the direction from the first mask wheel towards the sample, a beam conditioning unit 23 and a second mask wheel 25 are disposed after the first mask wheel. The beam conditioning unit 23 includes a flat gradient multilayer structure 10 and a Soller slit collimator fixed to the flat gradient multilayer structure 10. The flat gradient multilayer structure 10 reflects the incident X-ray beam without changing the divergence of the beam.

[0131] In one embodiment, the beam mask component 22 includes a mask wheel. Figure 1 The arrangement further includes a second mask wheel 25. Each mask wheel includes a body and has a plurality of masks formed in the body. Each mask wheel is rotatable about its center. The first mask wheel includes at least a first slit mask and an open beam mask. The first slit mask is used to limit the size of the beam (possibly in combination with other components). The open beam mask is a large opening sized to allow the X-ray beam to pass through uninterrupted. The first mask wheel may additionally include one or more other slit masks and / or attenuators. The controller 17 may be configured to control the position of the beam mask component.

[0132] By providing such an arrangement, the beam optics in the incident beam path can be conveniently reconfigured. Thus, the X-ray device can be used for a variety of different applications because different combinations of incident and diffracted beam optics can be provided without requiring a great deal of work by an expert user to reconfigure the device.

[0133] According to an embodiment of the present invention, the X-ray analysis device includes an adjustable slit 210 in the incident beam path between the X-ray tube 4 and the sample 6; and a non-adjustable another slit 220 in the incident beam path between the adjustable slit 210 and the sample 6. Under the control of the controller 17 (as shown by the dashed line in Figure 1 ), the adjustable slit 210 can be used as a programmable divergence slit. The non-adjustable slit 220 can be used as an anti-scatter slit (especially in combination with the adjustable slit 210), and / or it can be used as a fixed divergence slit.

[0134] According to an embodiment of the present invention, Figures 2 - 4 The cross-sectional view in Figure 2Shows the adjustable slit 210 when the controller 17 has set the adjustable slit 210 to the first width. The adjustable slit 210 is formed by two light-shielding plates (blades) 211 and 212 that face each other. The width of the adjustable slit is defined by the spacing between the two light-shielding plates. When the adjustable slit 210 is at the first width, the adjustable slit limits the divergence of the incident light beam to the first divergence angle α1. This is achieved by the light-shielding plates 211 and 212 blocking a part 122a of the light beam. The first divergence angle α1 is the divergence of the remaining part 12a of the incident light beam that is allowed to pass through the gap between the two light-shielding plates. By limiting the divergence in this way, the adjustable slit limits the area of the sample 6 that is irradiated by the incident light beam.

[0135] When the adjustable slit 210 is at the first width, the non-adjustable slit 220 does not interfere with the remaining part 12a of the incident light beam. In this embodiment, the non-adjustable slit 220 includes an opening in a solid plate material. The width of the fixed slit is defined by the spacing between the opposite sides of the opening. In Figure 2 the configuration shown (i.e., when the adjustable slit 210 is set to the first width), the remaining part 12a of the incident light beam passes through the opening, and the opposite sides of the opening do not interfere with or block the remaining part 12a of the incident light beam. However, the non-adjustable slit 220 can still be used as an anti-scattering slit in this configuration. Parasitic scattering from the adjustable slit 210 can be blocked by the two opposite sides of the solid plate. This is shown in Figure 2 by the scattered light 124 (represented by the dashed arrow), and the scattered light 124 is blocked by the non-adjustable slit 220 and thus prevented from reaching the sample.

[0136] Figure 3 Shows the adjustable slit 210 when the controller 17 has set the adjustable slit 210 to a second width (larger than the first width). At the second width, the adjustable slit 210 limits the divergence of the incident light beam to the second divergence angle α2, which is greater than the first divergence angle α1. This is achieved by the opposing light-shielding plates 211 and 212 blocking a part 122b of the light beam. The remaining part 12b of the light beam passes through the adjustable slit 210 to irradiate the sample 6. Again, by limiting the divergence of the incident light beam, the adjustable slit 210 limits the irradiated area of the sample 6.

[0137] When the adjustable slit 210 is at the second width, the non-adjustable slit 220 still does not interfere with the remaining part 12b of the incident light beam. That is, the light beam completely passes through the opening of the non-adjustable slit 220 without being blocked or interfered with. However, by blocking the parasitic scattered light 124 generated by the adjustable slit 210, the non-adjustable slit 220 can be used as an anti-scattering slit again.

[0138] Figure 4Shows the adjustable slit 210 when the controller 17 has set the adjustable slit 210 to a third width (greater than the first and second widths). At this third width, the adjustable slit 210 does not interfere with or block any part of the incident beam, and thus does not limit its divergence. However, as shown, the non-adjustable slit 220 now blocks a portion 122c of the beam, thereby limiting the divergence of the incident beam to a third divergence angle α3, which is greater than the first divergence angle α1 and the second divergence angle α2. Thus, when the adjustable slit 210 is at the third width, the non-adjustable slit 220 limits the irradiated area of the sample. This area is irradiated by the remaining portion 12c of the incident beam. Since the adjustable slit 210 does not interfere with the beam in this configuration, it does not generate any parasitic scattering.

[0139] Note that Figures 2 - 4 shows simplified, exaggerated geometries and is not intended to be to scale; they are only intended to explain the operating principle of the two slits 210 and 220. Additionally, for simplicity of explanation, Figures 2 - 4 shows the incident beam being directed vertically downward onto the sample in all three cases. In reality, it is more likely that the angle of incidence on the sample will vary, and by changing the width of the adjustable slit 210 according to the angle of incidence, the divergence of the incident beam will be controlled. Figure 5 This is shown in

[0140] In some embodiments, the apparatus further includes a goniometer (not shown), and the X-ray tube 4 (and the incident beam X-ray optics) are mounted to the goniometer so as to be rotatable about the axis of the goniometer. The sample is placed on the sample stage 8 so as to be aligned with the axis of the goniometer. The X-ray detector 14 (and the secondary beam X-ray optics) are also mounted to the goniometer such that they are rotatable about their axes. In one embodiment, the controller controls the combined goniometer and the adjustable slit 210 such that the adjustable slit 210 opens wider as the angle of incidence increases.

[0141] Figure 5 A particularly preferred example is shown in. When the goniometer is set to a first angle of incidence θ1, the controller sets the adjustable slit 210 to a first width, thereby producing an incident beam 12a having a first divergence angle α1. On the other hand, when the goniometer is set to a second, higher angle of incidence θ2 (as shown by the second position of the X-ray tube 4 in dashed lines), the controller sets the adjustable slit 210 to a second width in order to produce an incident beam 12b having a second, wider divergence angle α2. The width of the adjustable slit 210 is controlled, and thus the divergence angle α of the beam is controlled, such that the same, constant area of the sample is irradiated at the two angles of incidence. Although Figure 5This is shown for only two angles of incidence, but it will be apparent to those skilled in the art that the adjustable slit 210 can be controlled to provide this constant illumination area over a range of successive angles of incidence.

[0142] At a third, higher angle of incidence ( Figure 5 not shown), the adjustable slit 210 is set to a third width such that the opposing light shields 211 and 212 are fully moved out of the incident beam, and the non-adjustable slit 220 takes over from the adjustable slit 210 to determine the beam divergence. Once the non-adjustable slit 220 takes over, the divergence of the beam is fixed. This may be advantageous for measurements over a range of higher angles of incidence.

[0143] Typically, for X-ray analysis, the sample 6 is scanned over a range of angles of incidence θ (and the corresponding angles of the secondary beam detected by the detector 14). Since the slits 210 and 220 control the beam divergence by blocking a portion of the beam, the total amount of radiation falling on the sample varies with the different angles of incidence, even though the illumination area can be kept constant over a specific range of angles by controlling the adjustable slit 210. This results in a change in the total intensity of the X-rays received by the X-ray detector 14. To enable compensation for this, the controller can receive an output signal from the X-ray detector 14 and measure the intensity of the X-rays received by the detector 14. The controller can be configured to normalize the measured intensity according to the angle of incidence for which it measures the intensity. In particular, the controller 17 can be configured to normalize the measured intensity according to the width of the adjustable slit 210 when the adjustable slit controls the beam divergence, and to normalize the measured intensity according to the width of the other slit 220 when the other slit controls the beam divergence. In this way, the controller can automatically compensate for the change in the measured X-ray intensity caused by the hybrid divergence control system.

[0144] Note that in some embodiments, the compensation need not be performed by the controller 17. It can be performed by hardware, software, or firmware of another processor (not shown) independent of the controller 17. In this case, the other processor preferably receives information about the configuration of the slits 210 and 220, as well as the measured intensity to be normalized.

[0145] Figure 6 A method of X-ray analysis that can be performed according to an embodiment of the present invention using the X-ray analysis apparatus described above is shown.

[0146] When the method starts, a first angle of incidence to be measured is set in step 610. Next, in step 620, the controller 17 sets the width of the adjustable slit 210 according to the angle of incidence θ. This may correspond to the first width and the first angle of incidence θ1 described previously above. In this configuration, the adjustable slit 210 controls the divergence of the light beam. In step 630, the X-ray detector 14 is used to measure the intensity of the secondary light beam. In step 640, based on the width of the adjustable slit 210, the measured intensity is normalized (using the controller 17 or another processor) to compensate for the absence of the blocked portion 122a of the light beam.

[0147] In step 650, the method checks whether the threshold angle of incidence has been reached. This threshold angle corresponds to the point at which the non-adjustable slit 220 takes over from the adjustable slit 210 to control the divergence of the light beam. If the threshold angle has not been reached yet, the method returns to step 610, and the controller 17 controls the goniometer to move to the next angle of incidence. This may be the second angle of incidence θ2 described above. In this configuration, the adjustable slit 210 still controls the divergence of the light beam. Steps 620, 630, and 640 are repeated. This time, in step 640, the measured intensity is normalized based on the width of the adjustable slit 210 to compensate for the absence of the blocked portion 122b of the light beam.

[0148] When the threshold angle of incidence is reached, the method proceeds to step 660, and the controller 17 controls the goniometer to move to the next angle of incidence. The method is now in the constant angular divergence mode, where the divergence of the incident light beam is controlled by the non-adjustable slit 220. The shutter of the adjustable slit 210 no longer interferes with the incident light beam. Therefore, it is no longer necessary to set the width of the adjustable slit 210 according to the angle of incidence. The method proceeds directly to step 670, where the intensity of the secondary light beam is measured in step 670. This step is substantially the same as step 630 except for the way the divergence of the incident light beam is controlled. In step 680, based on the (fixed) width of the non-adjustable slit 220, the measured intensity is normalized (using the controller 17 or another processor) in order to compensate for the absence of the blocked portion 122c of the light beam.

[0149] In step 690, the method checks whether there are any other angles of incidence to be scanned. If so, the method returns to step 660 and steps 670 and 680 are repeated. When there are no longer any angles of incidence to be scanned, the method terminates.

[0150] Using this method allows for automatic scanning over a wide angular range and with different types of divergence control, where the divergence of the incident light beam (and thus the irradiated area of the sample) is controlled to give the best measurement results. The results are automatically normalized, so the use of different divergence control modes is transparent to the user. This may help avoid the need for expert users to perform complex post-processing of the results.

[0151] Note that, as in the case of using multiple divergence control modes on the same sample in the same scan (as described above), the apparatus according to embodiments of the present invention can be used to perform different scans in different modes. For example, the apparatus can be programmed to perform one type of scan using the non-adjustable slit 220 to control the divergence of the incident light beam. The apparatus can be programmed to perform another type of scan using the adjustable slit 210. The latter type of scan can be performed with the adjustable slit 210 set to a constant width (and thus a constant divergence) within a range of incident angles, or with the width (and thus the divergence) of the adjustable slit 210 varying according to the incident angle.

[0152] Figure 6A is a flowchart showing a Figure 6 variant of the method. In this variant, the width of the adjustable slit 210 varies at some incident angles and remains constant at other angles. In particular, it varies at lower angles and remains constant at higher angles. If desired, the method of this embodiment can be performed using only the adjustable slit 210. In other words, in this embodiment, the other slit 220 is optional.

[0153] Figure 6A Steps 610 to 650 in the method of Figure 6 are the same as steps 610 to 650 of Figure 6 However, in this embodiment, the threshold incident angle is still the angle at which the switch to the constant angular divergence mode is measured. However, different from the method of

[0154] Figure 7 is a schematic diagram showing an X-ray diffractometer according to another exemplary embodiment. This is Figure 1Variations of the illustrated embodiment. Except for the differences described below, this embodiment is the same as the embodiment of Figure 1 For the sake of brevity, the description of the common features will not be repeated.

[0155] In Figure 1 , another slit (non-adjustable slit 220) is located in the beam path between the adjustable slit 210 and the sample 6. This allows the non-adjustable slit 220 to be used as an anti-scattering slit to block the scattering generated by the adjustable slit 210. In particular, when the adjustable slit is set to the first width or the second width, it allows the non-adjustable slit 220 to block the scattering from the adjustable slit 210, where the adjustable slit limits the divergence of the incident beam. Since the adjustable slit 210 is typically used at its first width and second width at low incident angles, this can allow Figure 1 's device to provide good control of parasitic scattering at low incident angles.

[0156] In contrast, in Figure 7 , the order of the adjustable slit and another (non-adjustable) slit is reversed. In other words, the adjustable slit 210a is located in the incident beam path between the X-ray tube 4 and the sample 6; and another slit (non-adjustable slit 220) is located in the incident beam path between the X-ray tube 4 and the adjustable slit 210a. Similar to the embodiment of Figure 1 , the controller 17 controls the adjustable slit 210a.

[0157] Figure 7 's device can operate in a similar manner to Figure 1 . When the adjustable slit 210a is set to the first width and the second width, the adjustable slit 210a limits the beam divergence. When the adjustable slit 210a is set to the third width, another slit (non-adjustable slit 220) becomes the divergence-limiting component. However, now, the adjustable slit 210a can be used as an anti-scattering slit to block the parasitic scattering from the non-adjustable slit 220. In particular, when the adjustable slit 210a is set to the third width, it can be used as an anti-scattering slit, where the non-adjustable slit 220 limits the divergence of the incident beam. Since the adjustable slit 210a is typically used at its third width at high incident angles (as discussed above), this can allow Figure 7 's device to provide good control of parasitic scattering at high incident angles.

[0158] Therefore, the device of Figure 1 or Figure 7 can be selected according to whether it is more important to control parasitic scattering at low incident angles or at high incident angles in a specific application scenario. Optionally or additionally, the selection can depend on whether other optical elements in the beam path affect parasitic scattering.

[0159] In one embodiment, the controller 17 is preconfigured with information related to component configurations for different types of X-ray measurements. For example, the controller can be configured to perform measurements in the Bragg-Brentano mode, SAXS mode, GISAXS mode, thin film phase analysis mode, reflectometer mode, etc. For each type of X-ray measurement, there can be a specific associated component configuration (including the definition of how the incident beam divergence should be controlled with an adjustable slit and optionally another slit). The user selects a measurement mode, and the controller determines which configuration is appropriate by determining which configuration is associated with the selected measurement mode. The controller then sends control signals to one or more actuators such that the actuators move the components to that configuration. In some measurement modes, multiple configurations may be used. For example, when using the Bragg-Brentano geometry, measurements can be performed with a fixed illumination length or a fixed divergence or a combination of both (e.g., at different angles of incidence). The user can be prompted to select the desired measurement type, or the controller can make the selection based on other conditions and configure the adjustable slit (and optionally another slit) accordingly.

[0160] In another embodiment, the controller is preconfigured to select a component configuration based on the type of sample to be analyzed. For example, the user can input information identifying the type of sample to be analyzed. The controller compares this information with a database to determine the most appropriate component configuration. The database provides information on what type of scan is required for different materials and the appropriate component configuration for that scan.

[0161] In an embodiment, the component configuration is changed during a batch of measurements. In this embodiment, the sample holder includes a plurality of containers. Each container holds a different sample. The samples can be different materials. During the measurement, the sample holder is controlled to position a single container in the path of the incident X-ray beam. The controller controls the sample holder to move the container so as to replace the container disposed in the X-ray beam path with another container. In this way, X-ray measurements are performed on a batch of samples without user intervention. The controller is also configured to change the component configuration such that the configuration can be changed during a batch of measurements without user intervention.

[0162] Those skilled in the art will understand that variations of the embodiments discussed above can be provided. For example, in alternative embodiments, the following can be provided.

[0163] In some embodiments, as already mentioned above, another slit is not necessary and the divergence of the incident beam can be controlled solely by the adjustable slit. When present, it is not necessary for the other slit to be a non-adjustable slit with a fixed width. In some embodiments, it can be another adjustable slit. This can allow for a further degree of control over the scattering and / or angular divergence of the incident beam. The controller can be configured to control the width of the other adjustable slit based on the width of the (first) adjustable slit, based on the angle of incidence, or both. For example, the controller can be configured to increase the width of the other adjustable slit as the width of the (first) adjustable slit increases. The (first) adjustable slit can limit the divergence of the incident beam, and the other adjustable slit can control the parasitic scattering from the (first) adjustable slit without limiting the divergence of the incident beam (at least for some widths of the first adjustable slit). This can allow for a more effective control of the scattering from the first adjustable slit, since for each width of the first adjustable slit (i.e., for each divergence angle of the incident beam), the other adjustable slit can be controlled to be relatively close to the incident beam.

[0164] In the above embodiments, the non-adjustable other slit is provided by an opening in a solid plate material. However, this is not necessary. As is well known to those skilled in the art, there are other suitable types of slits that do not include an opening in a solid plate material.

[0165] Generally, all of the other X-ray optical devices mentioned in the above embodiments are optional. Depending on the application and / or the X-ray analysis to be performed, they may or may not be present in any given embodiment. This includes the beam conditioning unit 23 (including the flat graded multilayer structure 10 and the Soller slit collimator), the mask wheels 22 and 25, the first through fourth collimators, and the anti-scatter slit 11.

[0166] It should be noted that the embodiments mentioned above illustrate rather than limit the invention, and those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps other than those listed in the claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. An embodiment can be implemented by hardware comprising several distinct elements. In a device claim enumerating several means, several of these means can be embodied by one and the same item of hardware. The fact that certain means are recited in mutually different dependent claims does not indicate that a combination of these means cannot be used to advantage. Further, in the appended claims comprising "at least one of A; B; and C", "at least one of A; B; and C" should be construed as (A and / or B) and / or C.

[0167] In general, various embodiments can be implemented in hardware, or in dedicated circuitry, software, logic, or any combination thereof. For example, some aspects can be implemented in hardware, while other aspects can be implemented in firmware or software executable by a controller, microprocessor, or other computing device, without limitation to the examples. Although the various aspects described herein may be shown and described as block diagrams, flowcharts, or using some other graphical representation, it is well understood that the blocks, devices, systems, techniques, or methods described herein may be implemented as non-limiting examples in hardware, software, firmware, dedicated circuitry or logic, general-purpose hardware or controllers or other computing devices, or some combination thereof.

[0168] The embodiments described herein can be implemented by computer software executable by a data processor of the device (such as in a processor or controller), or by hardware, or by a combination of software and hardware. Additionally in this regard, it should be noted that any block in the logical flow in the figures can represent a program step, or an interconnected logic circuit, block, or function, or a combination of program steps and logic circuits, blocks, and functions. The software can be stored on a physical medium such as a storage chip or a memory block implemented within the processor, a magnetic medium (such as a hard disk or a floppy disk), and an optical medium (such as, for example, a DVD and its data variants, as well as a CD).

[0169] The memory can be of any type suitable for the local technical environment and can be implemented using any suitable data storage technology (such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory). As a non-limiting example, the data processor can be of any type suitable for the local technical environment and can include one or more of a general-purpose computer, a special-purpose computer, a microprocessor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), gate-level circuitry, and a processor based on a multi-core processor architecture.

Claims

1. An X-ray analysis device, comprising: an X-ray source (4) configured to generate X-rays; a sample stage (8) configured to support a sample (6), the X-ray source and the sample stage being arranged such that the X-rays generated by the X-ray source define an incident beam irradiating the sample; an adjustable slit (210) between the X-ray source and the sample; another slit (220) between the X-ray source and the adjustable slit, or between the adjustable slit and the sample; and a controller (17) configured to control the width of the adjustable slit, wherein the controller is configured to change the width of the adjustable slit between a first width, a second width, and a third width, the third width being greater than the second width, and the second width being greater than the first width, wherein at the first width: the adjustable slit limits the divergence of the incident beam to a first divergence angle, thereby limiting the irradiated area of the sample; at the second width: the adjustable slit limits the divergence of the incident beam to a second divergence angle, thereby limiting the irradiated area of the sample; and at the third width: the adjustable slit does not limit the divergence of the incident beam; and the another slit limits the divergence of the incident beam to a third divergence angle, thereby limiting the irradiated area of the sample, wherein the third divergence angle is greater than the second divergence angle, and the second divergence angle is greater than the first divergence angle.

2. The X-ray analysis apparatus according to claim 1, wherein, The another slit (220) is a non-adjustable slit.

3. The X-ray analysis apparatus according to claim 1, wherein, The another slit is adjustable.

4. The X-ray analysis apparatus according to any one of claims 1 to 3 further includes a goniometer, wherein, The X-ray source is mounted to the goniometer so as to be rotatable about the axis of the goniometer, thereby irradiating the sample at different incident angles within a range.

5. The X-ray analysis apparatus according to claim 4, wherein, The controller is configured to control the goniometer and the adjustable slit such that: when the goniometer is set to a first incident angle, the adjustable slit is set to the first width; when the goniometer is set to a second incident angle, the adjustable slit is set to the second width; and when the goniometer is set to a third incident angle, the adjustable slit is set to the third width, the third incident angle being greater than the second incident angle, and the second incident angle being greater than the first incident angle.

6. The X-ray analysis apparatus according to claim 5, wherein, The controller is configured to control the width of the adjustable slit such that within the range of the incident angle of the goniometer, the incident beam irradiates a constant area of the sample.

7. The X-ray analysis device according to claim 6, further comprising an X-ray detector (14) arranged to receive X-rays from the sample (6) and configured to generate an output signal measuring the intensity of the received X-rays, Among them, the controller being configured to receive the output signal from the X-ray detector and being configured to normalize the measured intensity by: when the adjustable slit is set to the first width or the second width, performing a first normalization calculation based on the width of the adjustable slit; and When the adjustable slit is set to the third width, a second normalization calculation is performed based on the width of the other slit.

8. The X-ray analysis apparatus according to claim 7, wherein, The X-ray analysis device is configured for X-ray fluorescence measurement.

9. The X-ray analysis apparatus according to claim 7, wherein, The X-ray analysis device is a diffractometer.

10. A method for X-ray analysis using a device, the device comprising: An X-ray source (4) configured to generate X-rays; A sample stage (8) configured to support a sample (6), the X-ray source and the sample stage being arranged such that the X-rays generated by the X-ray source define an incident beam irradiating the sample; An adjustable slit (210) between the X-ray source and the sample; Another slit (220) between the X-ray source and the adjustable slit, or between the adjustable slit and the sample; And A controller (17) configured to control the width of the adjustable slit, The method comprising: Setting, by the controller, the adjustable slit to a first width at which the adjustable slit limits the divergence of the incident beam to a first divergence angle, thereby limiting the irradiated area of the sample; Setting, by the controller, the adjustable slit to a second width at which the adjustable slit limits the divergence of the incident beam to a second divergence angle, thereby limiting the irradiated area of the sample; and Setting, by the controller, the adjustable slit to a third width at which the adjustable slit does not limit the divergence of the incident beam and the other slit limits the divergence of the incident beam to a third divergence angle, thereby limiting the irradiated area of the sample, wherein the third width is greater than the second width, and the second width is greater than the first width, and wherein the third divergence angle is greater than the second divergence angle, and the second divergence angle is greater than the first divergence angle.

11. A method for X-ray analysis using a device, the device comprising: An X-ray source (4) configured to generate X-rays; A sample stage (8) configured to support a sample (6), the X-ray source and the sample stage being arranged such that the X-rays generated by the X-ray source define an incident beam irradiating the sample; An adjustable slit (210) between the X-ray source and the sample; A goniometer, wherein the X-ray source is mounted to the goniometer for rotation about the axis of the goniometer to irradiate the sample at different incident angles within a range; and A controller (17) configured to control the goniometer and the width of the adjustable slit, The method comprising: When the goniometer is set to a first incident angle, setting, by the controller, the adjustable slit to a first width at which the adjustable slit limits the divergence of the incident beam to a first divergence angle, thereby limiting the irradiated area of the sample; When the goniometer is set to a second incident angle, the controller sets the adjustable slit to a second width, at which the adjustable slit limits the divergence of the incident light beam to a second divergence angle, thereby limiting the irradiated area of the sample; When the goniometer is set to a third incident angle, the controller sets the adjustable slit to a third width, at which the adjustable slit limits the divergence of the incident light beam to a third divergence angle, thereby limiting the irradiated area of the sample; and When the goniometer is set to a fourth incident angle, the controller sets the adjustable slit to the third width, wherein the third width is greater than the second width, and the second width is greater than the first width, wherein the third divergence angle is greater than the second divergence angle, and the second divergence angle is greater than the first divergence angle, and wherein the fourth incident angle is greater than the third incident angle, the third incident angle is greater than the second incident angle, and the second incident angle is greater than the first incident angle.

12. The method according to claim 11, wherein, The controller controls the width of the adjustable slit such that within a range of incident angles from the first incident angle to the second incident angle, the incident light beam irradiates a constant area of the sample.

13. The method according to claim 11 or 12, wherein, The device includes another slit (220) between the adjustable slit and the sample such that the incident light beam passes through the another slit, but the another slit does not limit the divergence of the incident light beam.

14. A computer-readable medium having a computer program stored thereon, the computer program including computer program code, the computer program being configured to cause the controller of an X-ray analysis device to perform all steps of the method according to any one of claims 10 to 13 when the computer program is run on the controller.

15. An X-ray analysis device, comprising: an X-ray source configured to generate X-rays; a sample stage configured to support a sample, the X-ray source and the sample stage being arranged such that the X-rays generated by the X-ray source define an incident light beam irradiating the sample; an adjustable slit between the X-ray source and the sample; a goniometer, wherein the X-ray source is mounted to the goniometer to irradiate the sample at different incident angles within a range; and a controller configured to control the goniometer and the width of the adjustable slit, wherein the controller is configured to change the width of the adjustable slit among a first width, a second width, and a third width, the third width being greater than the second width, the second width being greater than the first width, wherein, at the first width: the adjustable slit limits the divergence of the incident light beam to a first divergence angle, thereby limiting the irradiated area of the sample, at the second width: the adjustable slit limits the divergence of the incident light beam to a second divergence angle, thereby limiting the irradiated area of the sample, and at the third width: The adjustable slit limits the divergence of the incident light beam to a third divergence angle, thereby limiting the irradiated area of the sample. Wherein, the third divergence angle is greater than the second divergence angle, and the second divergence angle is greater than the first divergence angle. Wherein, the controller is configured to control the goniometer and the adjustable slit such that: When the goniometer is set to the first incident angle, the adjustable slit is set to the first width. When the goniometer is set to the second incident angle, the adjustable slit is set to the second width. When the goniometer is set to the third incident angle, the adjustable slit is set to the third width; and When the goniometer is set to the fourth incident angle, the adjustable slit is set to the third width. The fourth incident angle is greater than the third incident angle, the third incident angle is greater than the second incident angle, and the second incident angle is greater than the first incident angle.

16. The X-ray analysis device according to claim 15, further comprising an X-ray detector, the X-ray detector being arranged to receive X-rays from the sample and being configured to generate an output signal for measuring the intensity of the received X-rays.

17. The X-ray analysis apparatus according to claim 16, wherein, The controller is configured to receive the output signal from the X-ray detector and is configured to normalize the measured intensity by performing a normalization calculation based on the width of the adjustable slit when the adjustable slit is set to the first width, the second width, or the third width.

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