JP7701934B2 - Radiation detection module and radiation detection device - Google Patents

Description

The present invention relates to a radiation detection module including a plurality of radiation detection elements, and a radiation detection device.

Some radiation detectors that detect radiation such as X-rays include a radiation detection element that uses a semiconductor. The radiation detection element is plate-shaped, and a sensitive area capable of detecting radiation is present on the surface of the radiation detection element. Conventionally, in order to prevent radiation from entering areas other than the sensitive area, a collimator that limits the range into which radiation enters has been disposed on the surface of the radiation detection element. Conventional radiation detectors include a housing, and the radiation detection element and collimator are disposed inside the housing. Radiation detectors are used, for example, to irradiate a sample with radiation, detect radiation emitted from the sample, and analyze the components of the sample based on the detection results.

In order to improve the detection efficiency of radiation generated from a sample, the radiation detection element can be brought closer to the sample. However, due to the presence of a housing and a collimator, there is a lower limit to how close the radiation detection element can be to the sample. Patent Document 1 discloses a radiation detector that does not have a collimator, with the housing also functioning as the collimator. In such a radiation detector, the radiation detection element can be brought closer to the sample than a radiation detector with a collimator, improving detection efficiency.

International Publication No. 2019/117276

One method for improving the detection efficiency of radiation emitted from a sample is to detect radiation from the sample using multiple radiation detection elements. However, because the housings of the multiple radiation detectors interfere with each other, there is a lower limit to how close the radiation detection elements of the multiple radiation detectors can be to the sample. For this reason, there is a limit to how much the detection efficiency can be improved.

The present invention has been made in consideration of the above circumstances, and its purpose is to provide a radiation detection module and a radiation detection device that can bring multiple radiation detection elements close to a radiation source.

The radiation detection module according to the present invention comprises a block and a plurality of radiation detection elements attached to the block, the block having a plurality of first surfaces on which the radiation detection elements are attached, and a plurality of first through holes each having an opening at one end on each of the first surfaces for passing radiation, the radiation detection elements having an incident surface on which radiation is incident, and the radiation detection elements are attached to the first surface with the incident surface facing the first surface and with the openings of the first through holes in the first surface blocked.

In one embodiment of the present invention, the radiation detection module includes a block and a plurality of radiation detection elements. Each radiation detection element is attached to a respective one of a plurality of first surfaces of the block. A plurality of first through holes, each of which has an open end, is formed in the block. The radiation detection elements are attached to the first surface with the openings of the first through holes blocked. Radiation passes through the first through holes, enters the radiation detection elements, and is detected. The radiation that has passed through the first through holes enters the radiation detection elements. Therefore, the block serves as a collimator that limits the range into which the radiation enters. Since the block serves as a collimator, a collimator and a housing are not required. Since there is no housing, the housings do not interfere with each other, and the plurality of radiation detection elements can be closer to the source of radiation than before. Therefore, the efficiency of detecting radiation is improved.

In the radiation detection module of the present invention, the block further has a single second surface different from the plurality of first surfaces, and the other ends of the plurality of first through holes open into the second surface.

In one embodiment of the present invention, the block has a single second surface. The openings at the other ends of the multiple first through holes are formed in the second surface. By facing the second surface to a radiation source, the openings of the first through holes in the second surface face the radiation source. Radiation enters the first through holes, passes through the first through holes, enters the radiation detection element, and is detected.

The radiation detection module of the present invention is characterized in that straight lines perpendicular to each of the plurality of first surfaces intersect non-perpendicularly with the second surface.

In one embodiment of the present invention, a straight line perpendicular to each of the multiple first surfaces intersects the second surface non-perpendicularly. When the second surface faces the radiation source, the normal to the incident surface of the radiation detection element intersects the source. It is also possible to arrange the multiple radiation detection elements so that the source is located in front of each incident surface. In this state, the solid angle of the fluorescent X-rays incident on the incident surfaces of the multiple radiation detection elements becomes large.

The radiation detection module of the present invention is characterized in that the multiple first through holes are linear and extensions of the central axes of the multiple first through holes intersect with each other at a position in front of the second surface.

In one embodiment of the present invention, extensions of the central axes of the first through holes intersect with each other at a position in front of the bottom surface. When a radiation generating source is disposed at a position where the extensions of the central axes of the first through holes intersect, the generated radiation passes through the first through holes and is detected by the radiation detection elements.

In the radiation detection module of the present invention, the block has one end opening on the second surface and further has a second through hole for passing radiation irradiated to an external sample arranged opposite the second surface, the second through hole being linear, and an extension line of the central axis of the plurality of first through holes and an extension line of the central axis of the second through hole intersect at one point.

In one embodiment of the present invention, the block has a second through hole, and an opening at one end of the second through hole is formed on the second surface. The second surface is placed facing an external sample, and the primary radiation that has passed through the second through hole can be irradiated onto the sample. In addition, an extension line of the central axis of the multiple first through holes 114 and an extension line of the central axis of the second through hole intersect at one point. When the surface of the sample is placed at this one point, secondary radiation generated from a position where the intensity of the irradiated primary radiation is high is detected by the multiple radiation detection elements. As a result, the intensity of the detected secondary radiation is high.

In the radiation detection module of the present invention, the block has one end opening on the second surface and further has a second through hole for passing radiation irradiated to an external sample positioned opposite the second surface.

In one embodiment of the present invention, the block has a second through hole, and an opening at one end of the second through hole is formed in the second surface. The second surface is faced to an external sample, and the primary radiation that has passed through the second through hole can be irradiated onto the sample. Irradiation of the primary radiation generates secondary radiation from the sample, and the secondary radiation passes through the first through hole and is detected by the radiation detection element. The presence of the second through hole makes it possible to irradiate the sample with the primary radiation and detect the secondary radiation when the radiation detection module is close to the sample.

In the radiation detection module of the present invention, the openings of the multiple first through holes in the second surface are located in rotationally symmetric positions around the center of the second through hole in the second surface, and the multiple first through holes have the same length.

In one embodiment of the present invention, the openings of the multiple first through holes in the second surface are located at positions that are rotationally symmetrical about the center of the second through hole in the second surface, and the multiple first through holes have the same length. As a result, when the second surface is opposed to a radiation source, the distances from the radiation source along the radiation path to the multiple radiation detection elements are approximately equal. This allows the multiple radiation detection elements to detect radiation approximately evenly.

In the radiation detection module of the present invention, the multiple first surfaces are located in positions that are rotationally symmetrical about the second through hole, and the surface angles between each of the multiple first surfaces and the second surface are the same acute angle.

In one embodiment of the present invention, the face angle between each of the multiple first faces and the second face is an acute angle. This brings the multiple first faces closer to the radiation source, and allows the multiple radiation detection elements to be closer to the radiation source. In addition, the multiple first faces are located in rotationally symmetric positions with respect to the second through hole, and the face angles are the same. This makes the distances from the radiation source to the multiple first faces approximately uniform, and the distances from the radiation source to the multiple radiation detection elements approximately uniform. This makes it easy to equalize the distances from the radiation source to the multiple radiation detection elements along the radiation path.

In the radiation detection module of the present invention, the block has a shape in which each of the multiple side surfaces of a truncated pyramid is enlarged, the first surface is the enlarged side surface, and the second surface is the lower base surface of the truncated pyramid.

In one embodiment of the present invention, the block has a shape in which each side of a truncated pyramid is enlarged. The first face of the block corresponds to the enlarged side, and the second face corresponds to the lower base. By having the block in this shape, the positions of the multiple first faces can be rotationally symmetrical, and the face angles between each of the multiple first faces and the second face can be the same acute angle.

In the radiation detection module of the present invention, the incident surface includes a sensitive area capable of detecting radiation, the size of the opening of the first through hole in the first surface is equal to or smaller than the size of the sensitive area, and the radiation detection element is attached to the first surface with the sensitive area blocking the opening.

In one embodiment of the present invention, the size of the opening of the first through hole in the first surface is equal to or smaller than the size of the sensitive area of the incident surface of the radiation detection element. The opening of the first through hole can be blocked by the sensitive area, and the range into which radiation is incident is reliably limited to the sensitive area.

In the radiation detection module of the present invention, the material of the block is a ferromagnetic material, and a magnetic field generating mechanism is provided on the inner surface of the first through hole.

In one embodiment of the present invention, a magnetic field generating mechanism is provided on the inner surface of the first through hole. When electrons enter the radiation detection element through the first through hole, noise is generated. When a magnetic field is generated in the first through hole by the magnetic field generating mechanism, the direction of movement of electrons moving in the first through hole is bent by the magnetic field, making it difficult for them to enter the radiation detection element. This reduces noise. In addition, because the material of the block is a ferromagnetic material, the magnetic field does not leak outside the block, and even if the sample is a magnetic material, the sample will not be attracted to the block.

The radiation detection device of the present invention is characterized by comprising an irradiation unit that irradiates a sample with radiation, a radiation detection module of the present invention having a radiation detection element that detects radiation generated from the sample, and a spectrum generation unit that generates a spectrum of the radiation detected by the radiation detection element.

In one aspect of the present invention, the radiation detection device includes a radiation irradiation unit and a radiation detection module. Primary radiation from the irradiation unit is irradiated onto a sample, and secondary radiation generated from the sample is detected by radiation detection elements possessed by the radiation detection module. The multiple radiation detection elements can be brought closer to the sample than in the past, improving the efficiency of detecting secondary radiation. Therefore, the radiation detection device can improve the detection sensitivity of secondary radiation generated from the sample.

The radiation detection device according to the present invention is characterized in that it comprises an irradiation unit which irradiates a sample with radiation, a radiation detection module according to the present invention having a radiation detection element which detects radiation generated from the sample, a spectrum generation unit which generates a spectrum of the radiation detected by the radiation detection element, an analysis unit which performs an analysis of the sample based on the spectrum, and a display unit which displays the spectrum generated by the spectrum generation unit or the analysis results by the analysis unit.

In one embodiment of the present invention, the radiation detection device includes an irradiation unit, a radiation detection module, and an analysis unit. By improving the detection sensitivity of secondary radiation generated from a sample, the radiation detection device can perform highly accurate analysis of the sample based on the detection results of the secondary radiation.

In the present invention, multiple radiation detection elements can be brought closer to the radiation source than in the past. This improves the efficiency of radiation detection, and provides other excellent effects.

1 is a block diagram showing a configuration of a radiation detection apparatus according to a first embodiment. FIG. 2 is a schematic perspective view showing a radiation detection module. FIG. 2 is a schematic plan view showing a radiation detection module. FIG. 2 is a schematic perspective view showing a block. FIG. 2 is a schematic plan view showing a block. FIG. 2 is a schematic diagram showing the back side of the block. FIG. 2 is a schematic cross-sectional view showing a radiation detector. 2 is a schematic cross-sectional view showing the positional relationship between an X-ray optical element, a block, a radiation detection element, and a sample according to the first embodiment. FIG. 11 is a schematic cross-sectional view showing an example of a block and a radiation detector according to a second embodiment. FIG. 13 is a schematic cross-sectional view showing a first example of a block and a radiation detector according to a third embodiment. FIG. 13 is a schematic cross-sectional view showing a second example of the block and the radiation detector according to the third embodiment. FIG. FIG. 11 is a schematic cross-sectional view showing a block, a radiation detector, and a sample according to a fourth embodiment. FIG. 13 is a block diagram showing a configuration of a radiation detection apparatus according to a fifth embodiment.

The present invention will now be described in detail with reference to the drawings showing embodiments thereof.
<Embodiment 1>
FIG. 1 is a block diagram showing a configuration of a radiation detection device 10 according to a first embodiment. The radiation detection device 10 is an X-ray fluorescence analysis device. The radiation detection device 10 includes a sample stage 23 on which a sample 4 is placed, an X-ray source 21 that emits X-rays, which are primary radiation for irradiating the sample 4, an X-ray optical element 22 that converges the X-rays emitted by the X-ray source 21 and irradiates the sample 4, and a radiation detection module 1 including a plurality of radiation detection elements. The X-ray source 21 is, for example, an X-ray tube. The X-ray optical element 22 is, for example, a monocapillary lens using an X-ray guide tube that reflects and guides the incident X-rays inside, or a polycapillary lens using a plurality of X-ray guide tubes. The X-ray optical element 22 receives the X-rays emitted by the X-ray source 21 and converges the X-rays. The radiation detection module 1 is configured to pass the X-rays converged by the X-ray optical element 22. Details of the radiation detection module 1 will be described later.

The X-rays that pass through the radiation detection module 1 are irradiated onto the sample 4 placed on the sample stage 23. The X-ray source 21 and the X-ray optical element 22 correspond to the irradiation section. Fluorescent X-rays, which are secondary radiation, are generated in the portion of the sample 4 irradiated with the X-rays. The radiation detection element included in the radiation detection module 1 detects the fluorescent X-rays generated from the sample 4 and outputs a signal proportional to the energy of the detected fluorescent X-rays. In FIG. 1, the X-rays and fluorescent X-rays irradiated onto the sample 4 are indicated by solid arrows. Note that the radiation detection device 10 may be configured to hold the sample 4 by a method other than placing it on the sample stage 23.

A signal processing unit 31 that processes signals output by the radiation detection elements is connected to the radiation detection module 1. The signal processing unit 31 counts the signals of each value output by the radiation detection elements and performs processing to generate the relationship between the radiation energy and the count number, i.e., the radiation spectrum. The signal processing unit 31 corresponds to the spectrum generation unit.

The signal processing unit 31 is connected to the analysis unit 33. The analysis unit 33 is configured to include a calculation unit that performs calculations and a memory that stores data. The signal processing unit 31 outputs data indicating the generated spectrum to the analysis unit 33. The analysis unit 33 receives data from the signal processing unit 31 and performs qualitative or quantitative analysis of elements contained in the sample 4 based on the spectrum indicated by the input data. For example, the analysis unit 33 may analyze the amount of impurities contained in the sample 4. A display unit 34 such as a liquid crystal display is connected to the analysis unit 33. The display unit 34 displays the analysis results by the analysis unit 33. The display unit 34 also displays the spectrum generated by the signal processing unit 31. Note that the radiation detection device 10 may be configured such that the signal processing unit 31 does not generate a spectrum, and the analysis unit 33 generates a spectrum. In this configuration, the analysis unit 33 corresponds to a spectrum generation unit.

A drive unit 35 that moves the sample stage 23 is connected to the sample stage 23. The drive unit 35 is configured using, for example, a stepping motor. The drive unit 35 moves the sample stage 23 one-dimensionally, two-dimensionally, or three-dimensionally. For example, the drive unit 35 moves the sample stage 23 in the horizontal plane direction. The drive unit 35 moves the sample stage 23 to move the sample 4 and change the position on the sample 4 where the X-rays are irradiated.

The signal processing unit 31, the analysis unit 33, the drive unit 35, and the X-ray source 21 are connected to the control unit 32. The control unit 32 controls the operation of the signal processing unit 31, the analysis unit 33, the drive unit 35, and the X-ray source 21. The control unit 32 may cause the X-ray source 21 to emit X-rays while causing the drive unit 35 to move the sample 4, cause the signal processing unit 31 to generate a spectrum, and cause the analysis unit 33 to generate a spectral distribution or an elemental distribution on the sample 4. The display unit 34 may display the spectral distribution or the elemental distribution. The control unit 32 may be configured to receive a user's operation and control each unit of the radiation detection device 10 in response to the received operation. The control unit 32 and the analysis unit 33 may also be configured as a single computer.

Fig. 2 is a schematic perspective view showing the radiation detection module 1. Fig. 3 is a schematic plan view showing the radiation detection module 1. The radiation detection module 1 comprises a block 11 and a plurality of radiation detectors 12. The plurality of radiation detectors 12 are attached to the block 11. The radiation detectors 12 include radiation detection elements.

Figure 4 is a schematic perspective view showing the block 11. Figure 5 is a schematic plan view showing the block 11. Figure 6 is a schematic view showing the back side of the block 11. Figure 6 shows a view of the block 11 shown in Figure 4 from the back side. The block 11 is made of a solid material such as a metal. For example, it is desirable that the material of the block 11 is a material that has a small effect on the analysis due to the system peak. The system peak is a peak caused by the fluorescent X-ray generated from the block 11 among the peaks contained in the spectrum. For example, the material of the block 11 is a light element such as aluminum. Alternatively, the material of the block 11 may be a material that shields radiation, such as brass. The block 11 has a truncated pyramid shape. In the first embodiment, an example is shown in which the block 11 has a truncated triangular pyramid shape. More specifically, the block 11 has a shape in which each side of a truncated pyramid with multiple side surfaces congruent is expanded. Each side surface expands in a direction that does not intersect with the virtual extension plane of the upper base surface and the virtual extension plane of the lower base surface. In addition, the multiple side surfaces have an enlarged shape while maintaining rotational symmetry with respect to the axis of rotational symmetry of the truncated pyramid.

4 and 5, the block 11 has a top surface 111 corresponding to the upper base surface of the truncated pyramid, and a plurality of mounting surfaces (first surfaces) 113 which are enlarged sides of the truncated pyramid. The mounting surfaces 113 are surfaces on which the radiation detectors 12 are mounted. As shown in Fig. 6, the block 11 has a bottom surface (second surface) 115 corresponding to the lower base surface of the truncated pyramid. The shape of the block 11 may be that of a truncated pyramid with non-enlarged sides.

The radiation detection module 1 is disposed between the X-ray optical element 22 and the sample stage 23. The top surface 111 faces the tip of the X-ray optical element 22, and the bottom surface 115 faces the mounting surface of the sample stage 23. When a sample 4 is placed on the sample stage 23, the bottom surface 115 faces the surface of the sample 4.

The radiation detection module 1 has first through holes 114 formed therein, each penetrating from the bottom surface 115 to each mounting surface 113. That is, the radiation detection module 1 has a plurality of first through holes 114. The first through holes 114 are formed linearly. One end of each of the first through holes 114 opens to the respective mounting surface 113. The other ends of the plurality of first through holes 114 open to the bottom surface 115.

The radiation detection module 1 is formed with a second through hole 112 penetrating from the top surface 111 to the bottom surface 115. The second through hole 112 is formed linearly. One end of the second through hole 112 opens to the bottom surface 115, and the other end opens to the top surface 111. In this embodiment, an example is shown in which the opening at one end of the second through hole 112 is located at the center of gravity of the bottom surface 115, and the opening at the other end is located at the center of gravity of the top surface 111.

6, the opening of the second through hole 112 in the bottom surface 115 and the openings of the multiple first through holes 114 in the bottom surface 115 form an opening 116 that is connected to each other. The radiation detection module 1 is arranged so that the opening of the second through hole 112 in the top surface 111 faces the tip of the X-ray optical element 22, and the opening 116 faces the mounting surface of the sample stage 23. When the sample 4 is placed on the sample stage 23, the opening 116 faces the surface of the sample 4. The opening of the second through hole 112 in the bottom surface 115 and the openings of the multiple first through holes 114 in the bottom surface 115 do not have to be connected. Even in this form, each opening faces the surface of the sample 4. It is desirable that the openings of the multiple first through holes 114 in the bottom surface 115 are in rotational symmetry with each other about the center of the second through hole 112 in the bottom surface 115, whether they are connected or not. It is also preferable that the lengths of the plurality of first through holes 114 are the same. The tip of the X-ray optical element 22 may be inserted into the second through hole 112.

Figure 7 is a schematic cross-sectional view showing the radiation detector 12. The radiation detector 12 has a substrate 121 and a radiation detection element 122. The radiation detection element 122 is plate-shaped and arranged on the substrate 121. The radiation detection element 122 is a semiconductor radiation detection element such as an SDD (Silicon Drift Detector). The radiation detection element 122 generates an electric charge according to the energy of the incident radiation and outputs a current signal according to the generated electric charge. The material of the substrate 121 is, for example, synthetic resin, glass, or ceramic. The substrate 121 is provided with a circuit necessary for the radiation detection element 122 to operate. The circuit includes various components such as an amplifier that converts or amplifies the signal output by the radiation detection element 122. The circuit provided on the substrate 121 and the radiation detection element 122 are electrically connected. In addition, the circuit provided on the substrate 121 and the signal processing unit 31 are electrically connected. The signal output from the radiation detection element 122 is input to the signal processing unit 31 via a circuit provided on the substrate 121 .

The radiation detector 12 may be provided with a temperature regulator that adjusts the temperature of the radiation detection element 122, and may be configured to regulate the temperature of the radiation detection element 122 to a constant temperature such as 30°C by the temperature regulator. By keeping the temperature of the radiation detection element 122 constant, the accuracy with which the radiation detection element 122 detects radiation is stabilized. The radiation detector 12 may be configured not to include a temperature regulator.

The radiation detection element 122 has an incident surface 125 on which the radiation to be detected is incident. The radiation detection element 122 is arranged on the substrate 121 so that the rear surface of the incident surface 125 faces the surface of the substrate 121. The incident surface 125 includes a sensitive area 123 capable of detecting radiation and an insensitive area 124 that is not used for detecting radiation. The sensitive area 123 occupies an area including the center of the incident surface 125. The radiation detector 12 is mounted on the block 11 so that the incident surface 125 of the radiation detection element 122 faces the mounting surface 113. Furthermore, the radiation detector 12 is mounted on the block 11 with the incident surface 125 of the radiation detection element 122 blocking the opening of the first through hole 114 in the mounting surface 113. That is, the radiation detection element 122 is mounted on the mounting surface 113 so that the incident surface 125 faces the mounting surface 113 and in a state in which the opening of the first through hole 114 in the mounting surface 113 is blocked. Therefore, the incident surface 125 of the radiation detection element 122 faces the opening of the first through hole 114. Figures 2 and 3 show the radiation detector 12 mounted on the block 11, and the back surface of the substrate 121 on which the radiation detection element 122 is arranged on the surface can be seen.

Figure 8 is a schematic cross-sectional view showing the positional relationship between the X-ray optical element 22, the block 11, the radiation detection element 122, and the sample 4 according to the first embodiment. Figure 8 shows a cross-section of the radiation detection module 1 cut along the line VIII-VIII shown in Figure 3. As described above, the opening of the second through hole 112 in the top surface 111 faces the tip of the X-ray optical element 22, and the opening 116 faces the surface of the sample 4. Therefore, the X-rays converged by the X-ray optical element 22 pass through the second through hole 112 and are irradiated to the sample 4. Fluorescent X-rays are generated radially from the sample 4 irradiated with X-rays. The portion of the sample 4 irradiated with X-rays becomes the source of fluorescent X-rays. In Figure 8, X-rays and fluorescent X-rays are indicated by solid arrows. The presence of the second through hole 112 allows the radiation detection module 1 to irradiate X-rays to the sample 4 when it is close to the sample 4. Even when the tip of the X-ray optical element 22 is inserted into the second through hole 112, the X-rays are converged by the X-ray optical element 22, pass through the second through hole 112, and are irradiated onto the sample 4.

The bottom surface 115 faces the sample 4, and the opening 116 faces the sample 4, so that the fluorescent X-rays generated from the sample 4 penetrate the first through-hole 114 from the opening 116 and pass through the first through-hole 114. The entrance surface 125 of the radiation detection element 122 faces the opening of the first through-hole 114 in the mounting surface 113, so that the fluorescent X-rays are incident on the entrance surface 125. The radiation detection element 122 detects the incident fluorescent X-rays and outputs a signal. In each of the multiple radiation detection elements 122, the fluorescent X-rays that have passed through the first through-hole 114 are detected and a signal is output. The signal processing unit 31 counts the signals of each value output by the radiation detection element 122 and generates a spectrum. The analysis unit 33 performs an analysis based on the spectrum. The drive unit 35 may move the sample 4, and the analysis unit 33 may generate a spectral distribution or an element distribution. For example, the analysis unit 33 may analyze the distribution of impurities contained in the sample 4. The display unit 34 displays the analysis results.

The multiple mounting surfaces 113 are located in rotational symmetry with respect to each other with the second through hole 112 as the center. More precisely, the multiple mounting surfaces 113 may be located in rotational symmetry with the central axis of the second through hole 112 as the central axis. The surface angle between each of the multiple mounting surfaces 113 and the bottom surface 115 is the same acute angle. The mounting surfaces 113 and the bottom surface 115 do not have to directly intersect. The surface angle between the virtual extension surface of each of the multiple mounting surfaces 113 and the bottom surface 115, the surface angle between each of the multiple mounting surfaces 113 and the virtual extension surface of the bottom surface 115, or the surface angle between the virtual extension surface of each of the multiple mounting surfaces 113 and the virtual extension surface of the bottom surface 115 may be the same acute angle.

The mounting surface 113 and the bottom surface 115 are arranged so that a straight line perpendicular to each of the multiple mounting surfaces 113 intersects the bottom surface 115 non-perpendicularly. In addition, the multiple mounting surfaces 113 are non-parallel to each other. When the bottom surface 115 faces the sample 4, the normal to the incident surface 125 of the radiation detection element 122 intersects the surface of the sample 4, and the sample 4 is located in front of the incident surface 125. In this state, the solid angle of the fluorescent X-rays generated from the sample 4 and incident on the incident surface 125 is larger than when the normal to the incident surface 125 does not intersect the surface of the sample 4. Therefore, the efficiency of detecting the fluorescent X-rays from the sample 4 by the radiation detection element 122 is increased. In addition, the multiple mounting surfaces 113 are located around the straight line perpendicular to the bottom surface 115 so that the straight line perpendicular to the mounting surface 113 intersects the bottom surface 115 non-perpendicularly, and thus the multiple radiation detection elements 122 are arranged so that the sample 4 is located in front of each incident surface 125. The solid angle of the fluorescent X-rays generated from the sample 4 and incident on the incident surfaces 125 of the plurality of radiation detection elements 122 becomes large, and the efficiency of detecting the fluorescent X-rays from the sample 4 increases.

It is preferable that the bottom surface 115 and the first through holes 114 are configured so that the extension lines of the central axes of the multiple first through holes 114 intersect with each other at a position in front of the bottom surface 115. It is more preferable that the extension lines of the central axes of the multiple first through holes 114 all intersect at one point. The position where the extension lines of the central axes of the multiple first through holes 114 intersect is close to the bottom surface 115 and is spaced from the bottom surface 115 in the front direction of the bottom surface 115. When the surface of the sample 4 is placed at the position where the extension lines of the central axes of the multiple first through holes 114 intersect, fluorescent X-rays generated from the same part of the sample 4 pass through the multiple first through holes 114 and are detected by the multiple radiation detection elements 122. Therefore, the efficiency of detecting fluorescent X-rays from the sample 4 by the radiation detection elements 122 is increased.

More preferably, the bottom surface 115, the first through hole 114, and the second through hole 112 are configured so that the extension line of the central axis of the plurality of first through holes 114 and the extension line of the central axis of the second through hole 112 intersect at one point. The position where the extension line of the central axis of the plurality of first through holes 114 and the extension line of the central axis of the second through hole 112 intersect at one point is close to the bottom surface 115 and is located away from the bottom surface 115 in the front direction of the bottom surface 115. The intensity of the X-ray irradiated to the sample 4 is maximum on the central axis of the second through hole 112. When the surface of the sample 4 is arranged at the position where the extension line of the central axis of the plurality of first through holes 114 and the extension line of the central axis of the second through hole 112 intersect at one point, the fluorescent X-ray generated from the position where the intensity of the irradiated X-ray is large is detected by the plurality of radiation detection elements 122. The intensity of the detected fluorescent X-ray increases according to the intensity of the irradiated X-ray. Therefore, the fluorescent X-rays generated from the sample 4 can be detected efficiently.

Fluorescent X-rays that have passed through the first through-hole 114 are incident on the incident surface 125 of the radiation detection element 122. For this reason, the block 11 serves as a collimator that limits the range of the incident surface 125 into which the fluorescent X-rays are incident to the sensitive region 123. It is desirable that the size of the opening of the first through-hole 114 in the mounting surface 113 is equal to or smaller than the size of the sensitive region 123, and it is desirable that the radiation detection element 122 is mounted on the mounting surface 113 with the sensitive region 123 blocking the opening. For example, the shape and size of the opening of the first through-hole 114 may be the same as the shape and size of an area of the sensitive region 123 that has a relatively high X-ray detection sensitivity. In this state, the range into which the fluorescent X-rays are incident is reliably limited to the sensitive region 123.

The edge of the opening of the first through hole 114 on the mounting surface 113 may be provided with a shielding portion made of a material that has a higher performance of shielding radiation such as X-rays than the material of the block 11. For example, the material of the block 11 is aluminum, and the shielding portion is made of brass. For example, the shielding portion is provided in a ring shape on the edge of the opening of the first through hole 114 on the mounting surface 113. The shielding portion effectively prevents the fluorescent X-rays from spreading beyond the opening of the first through hole 114, thereby further improving the performance of the block 11 as a collimator. Alternatively, the shielding portion may be provided on the inner surface of the first through hole 114. The shielding portion is provided from the opening on the mounting surface 113 to the inside of the block 11. Even in this form, the shielding portion effectively prevents the fluorescent X-rays from spreading, thereby further improving the performance of the block 11 as a collimator. The shielding portion prevents X-rays from hitting the block 11, and the fluorescent X-rays generated from the block 11 are blocked to some extent by the shielding portion, so that the system peak caused by the fluorescent X-rays generated from the block 11 is reduced.

The inner surface of the first through hole 114 may be provided with a coating made of a material that has better radiation shielding properties than the material of the block 11. For example, the material of the block 11 is aluminum, and the inner surface of the first through hole 114 is coated with brass. The coating provides more effective radiation shielding, further improving the performance of the block 11 as a collimator.

A second coating may be provided on the first coating provided on the inner surface of the first through hole 114 to block secondary radiation generated from the first coating. A third coating may be provided on the second coating to block secondary radiation generated from the second coating. In order to reduce the intensity of the secondary radiation generated, it is desirable that the material of the second coating is a material with a smaller atomic number than the material of the first coating, and it is desirable that the material of the third coating is a material with a smaller atomic number than the material of the second coating. For example, the material of the second coating is aluminum, and the material of the third coating is fluororesin. Radiation is more effectively blocked, the performance of the block 11 as a collimator is improved, and the system peak is reduced.

Since the block 11 serves as a collimator, the radiation detector 12 does not require a collimator or a housing. Since the multiple radiation detectors 12 do not have housings, the housings do not interfere with each other, and the housings do not interfere with the sample 4. Therefore, compared to the conventional case, the multiple radiation detection elements 122 provided in the multiple radiation detectors 12 can be brought closer to the sample 4, which is the source of the fluorescent X-rays. By bringing the multiple radiation detection elements 122 closer to the sample 4, the efficiency of detecting the fluorescent X-rays generated from the sample 4 is improved. Therefore, the radiation detection device 10 can improve the detection sensitivity of the fluorescent X-rays generated from the sample 4. By improving the detection sensitivity of the fluorescent X-rays, the radiation detection device 10 can perform analysis of the sample 4 based on the fluorescent X-rays with high accuracy.

The openings of the first through holes 114 in the bottom surface 115 are located in positions that are rotationally symmetrical to one another around the center of the second through hole 112 in the bottom surface 115, and the lengths of the first through holes 114 are the same. Therefore, when the opening 116 is opposed to the sample 4, the distances from the sample 4 to the radiation detection elements 122 along the path of the fluorescent X-rays are approximately equal. Therefore, the fluorescent X-rays can be detected approximately evenly by the radiation detection elements 122. There is no need to correct the intensity of the fluorescent X-rays detected by the radiation detection elements 122 according to the distance, and the intensity of the fluorescent X-rays can be calculated by a simple calculation.

The surface angle between each of the multiple mounting surfaces 113 and the bottom surface 115 is an acute angle, so that the multiple mounting surfaces 113 approach the sample 4, and the multiple radiation detection elements 122 can be brought closer to the sample 4. The multiple mounting surfaces 113 are located in rotational symmetry with respect to the second through hole 112, and the above-mentioned surface angles are the same, so that the distances from the sample 4 to the multiple mounting surfaces 113 are approximately equal, and the distances from the sample 4 to the multiple radiation detection elements 122 are approximately equal. This makes it easy to equalize the distances from the sample 4 to the multiple radiation detection elements 122 along the fluorescent X-ray path.

In this embodiment, the radiation detection device 10 is shown to have a driving unit 35, but the radiation detection device 10 may have a configuration that does not have a driving unit 35. In this configuration, the radiation detection device 10 irradiates a point on the sample 4 with X-rays and detects fluorescent X-rays generated from the point.

<Embodiment 2>
In the second embodiment, the first through hole 114 is expanded toward the radiation detection element 122. FIG. 9 is a schematic cross-sectional view showing an example of the block 11 and the radiation detector 12 according to the second embodiment. The configuration of the radiation detection device 10 other than the block 11 is the same as that of the first embodiment. The inner diameter of the first through hole 114 gradually expands from the bottom surface 115 toward the mounting surface 113, and is larger as it approaches the mounting surface 113. For example, the inner surface of the first through hole 114 forms a truncated cone surface. The opening of the first through hole 114 on the mounting surface 113 is larger than that of the first embodiment. Since the opening of the first through hole 114 is larger, when a radiation detection element 122 having a wider sensitive region 123 than that of the first embodiment is mounted on the mounting surface 113, the radiation detection element 122 can detect radiation over a wider area.

If the inner diameter of the first through hole 114 is widened overall, the area where the block 11 does not shield radiation will be widened, and the performance of the block 11 as a collimator will be reduced. In the second embodiment, the inner diameter of the first through hole 114 is small in the area close to the bottom surface 115, and the inner diameter of the first through hole 114 becomes larger as it approaches the radiation detection element 122, so that the expansion of the area where the block 11 does not shield radiation can be suppressed. Therefore, the radiation detection element 122 can detect radiation over a wide area while suppressing the deterioration of the performance of the block 11 as a collimator. The radiation detection element 122 detects radiation over a wide area, thereby improving the detection sensitivity of radiation. Therefore, the radiation detection device 10 can further improve the detection sensitivity of fluorescent X-rays generated from the sample 4.

Furthermore, in embodiment 2, it is possible to use radiation detection elements 122 with a wide sensitive area 123 without making the block 11 larger than in embodiment 1. Therefore, the distance between the sample 4 and the radiation detection elements 122 does not increase compared to embodiment 1, and the detection sensitivity of the fluorescent X-rays does not decrease due to the increase in distance. Therefore, the detection sensitivity of the fluorescent X-rays generated from the sample 4 is further improved, and the radiation detection device 10 can perform analysis of the sample 4 based on the fluorescent X-rays with higher accuracy.

<Embodiment 3>
In the third embodiment, the mounting surface 113 and the radiation detection element 122 are separated from each other. An electric signal flows through the incident surface 125 of the radiation detection element 122. If the material of the block 11 is a conductor such as a metal, a current may flow through the block 11. Therefore, if the block 11 and the incident surface 125 come into contact with each other, a current flows between the block 11 and the radiation detection element 122, and noise is generated in the signal output by the radiation detection element 122.

Figure 10 is a schematic cross-sectional view showing a first example of the block 11 and the radiation detector 12 according to the third embodiment. The configuration of the radiation detection device 10 other than the block 11 and the radiation detector 12 is the same as that of the first or second embodiment. A gap 126 is provided between the incident surface 125 of the radiation detection element 122 and the mounting surface 113. The radiation detector 12 is fixed to the block 11 by a screw 127 that penetrates the substrate 121 and is inserted into the block 11 from the mounting surface 113. The screw 127 fixes the radiation detector 12 to the block 11 while maintaining the gap 126. Due to the presence of the gap 126, the incident surface 125 is not in contact with the block 11. Therefore, no current flows between the block 11 and the radiation detection element 122, and no noise is generated in the signal output by the radiation detection element 122.

Figure 11 is a schematic cross-sectional view showing a second example of the block 11 and the radiation detector 12 according to the third embodiment. The configuration of the radiation detection device 10 other than the block 11 and the radiation detector 12 is the same as that of the first or second embodiment. An insulating layer 128 made of an insulator is provided between the incident surface 125 of the radiation detection element 122 and the mounting surface 113. The radiation detector 12 is fixed to the block 11 by a screw 127. The radiation detector 12 may be fixed to the block 11 without the screw 127. For example, the insulating layer 128 may be bonded to the mounting surface 113, and the radiation detection element 122 may be bonded to the insulating layer 128. Due to the presence of the insulating layer 128 between the incident surface 125 and the mounting surface 113, no current flows between the block 11 and the radiation detection element 122, and no noise occurs in the signal output by the radiation detection element 122.

In the third embodiment, the block 11 also functions as a collimator, thereby improving the detection sensitivity of the fluorescent X-rays generated from the sample 4. In the third embodiment, the generation of noise caused by the current flowing between the block 11 and the radiation detection element 122 can be prevented, thereby further improving the radiation detection sensitivity. Therefore, the radiation detection device 10 can perform analysis of the sample 4 based on the fluorescent X-rays with higher accuracy.

<Embodiment 4>
FIG. 12 is a schematic cross-sectional view showing the block 11, the radiation detector 12, and the sample 4 according to the fourth embodiment. The arrows in the figure indicate fluorescent X-rays generated from the sample 4. The configuration of the radiation detection device 10 other than the block 11 is the same as that of the first to third embodiments. In the fourth embodiment, an electron trap 117 (magnetic field generating mechanism) is provided on the inner surface of the first through hole 114. The electron trap 117 is configured by arranging a plurality of permanent magnets on the inner surface of the first through hole 114 so as to face each other. The permanent magnets are attached to the inner surface of the first through hole 114 or embedded in the block 11 in a state in which a magnetic field is generated in the first through hole 114. The permanent magnets cause the electron trap 117 to generate a magnetic field in the first through hole 114. The electron trap 117 corresponds to the magnetic field generating mechanism.

In addition to fluorescent X-rays, electrons may be generated as secondary radiation from the sample 4. When the generated electrons enter the radiation detection element 122, noise occurs in the signal output by the radiation detection element 122. When the electron trap 117 is generating a magnetic field within the first through-hole 114, the direction of movement of the electrons moving within the first through-hole 114 is bent by the magnetic field. For this reason, the direction of movement of the electrons generated from the sample 4 is bent on the way to the radiation detection element 122, making it difficult for them to enter the radiation detection element 122. The number of electrons entering the radiation detection element 122 is reduced, and the noise generated in the signal output by the radiation detection element 122 is reduced.

In embodiment 4, the material of block 11 is a ferromagnetic material such as iron or nickel. If the material of block 11 is not a ferromagnetic material, the magnetic field generated by electron trap 117 will leak outside block 11. If sample 4 is a magnetic material, sample 4 will be attracted to block 11 by the magnetic field. In embodiment 4, since the material of block 11 is a ferromagnetic material, the magnetic field generated by electron trap 117 is blocked by block 11 and will not leak outside block 11. Therefore, sample 4 will not be attracted to block 11, and a magnetic material can be used as sample 4. Therefore, sample 4 is not restricted.

The electron trap 117 may be configured to generate a magnetic field by a method other than using a permanent magnet. For example, the electron trap 117 may be configured using an electromagnet. In the fourth embodiment, the block 11 also functions as a collimator, thereby improving the detection sensitivity of the fluorescent X-rays generated from the sample 4. In the fourth embodiment, noise caused by electrons entering the radiation detection element 122 is reduced, thereby further improving the detection sensitivity of the radiation. Therefore, the radiation detection device 10 can perform analysis of the sample 4 based on the fluorescent X-rays with higher accuracy.

<Embodiment 5>
13 is a block diagram showing the configuration of the radiation detection device 10 according to the fifth embodiment. In the fifth embodiment, the radiation detection device 10 does not include the sample stage 23 and the driving unit 35. The sample 4 is a long sheet, and is moved by rollers 41 in the direction shown by the outlined arrow. The radiation detection module 1 is disposed so that the opening 116 faces the surface of the sample 4. The configuration of the other parts of the radiation detection device 10 is similar to that of the first to fourth embodiments. It is desirable that the extension lines of the central axes of the multiple first through holes 114 intersect with each other on the surface of the sample 4. It is more desirable that the extension lines of the central axes of the multiple first through holes 114 and the extension line of the central axis of the second through hole 112 intersect at one point on the surface of the sample 4.

The sample 4 moves continuously, and X-rays from the X-ray source 21 are irradiated onto the sample 4 via the X-ray optical element 22 and the radiation detection module 1. As the sample 4 moves, X-rays are sequentially irradiated onto multiple parts of the sample 4, and fluorescent X-rays are sequentially generated from each part. The multiple radiation detection elements 122 of the radiation detection module 1 sequentially detect the fluorescent X-rays generated from the sample 4, and the analysis unit 33 sequentially performs analysis. In FIG. 13, X-rays and fluorescent X-rays are indicated by solid arrows. For example, based on the intensity of the fluorescent X-rays detected by the radiation detection elements 122, the analysis unit 33 analyzes the amount of impurities contained in the sample 4. For example, the analysis unit 33 analyzes the thickness of the sample 4 from the intensity of the detected fluorescent X-rays, utilizing the fact that the intensity of the fluorescent X-rays of the base material of the sample 4 changes depending on the thickness of the sample 4.

In the radiation detection device 10 of the fifth embodiment, the radiation detection elements 122 can be brought closer to the sample 4 than in the past, and the efficiency of detecting fluorescent X-rays generated from the sample 4 is improved. Therefore, the radiation detection device 10 has high detection sensitivity for fluorescent X-rays generated from the sample 4, and the time required to detect the fluorescent X-rays is short. For example, the sample 4 is an industrial product, and the radiation detection device 10 can be used to measure the amount of impurities or the thickness of the sample 4, and an abnormality in the sample 4 can be determined according to the amount of impurities or the thickness of the sample 4. Since the radiation detection device 10 requires a short time to detect fluorescent X-rays generated from the sample 4, the time required to determine an abnormality in the sample 4 is also short. Therefore, the movement time of the sample 4 when determining an abnormality in the sample 4 can be made faster. Therefore, by using the radiation detection device 10 according to the fifth embodiment, it is possible to efficiently produce and inspect the sample 4.

In the above embodiments 1 to 5, the radiation detection device 10 is shown to have the X-ray optical element 22, but the radiation detection device 10 may not have the X-ray optical element 22. In this embodiment, the block 11 serves as a collimator that limits the range in which the sample 4 is irradiated with X-rays. In the above embodiments 1 to 5, the radiation detection module 1 is shown to have three radiation detection elements 122, but the block 11 may have two or four or more mounting surfaces 113, and the radiation detection device 10 may have two or four or more radiation detection elements 122. In the above embodiments 1 to 5, the block 11 is shown to have a truncated pyramid shape, but the block 11 may have another shape. The shape of the mounting surface 113 may be a shape other than a rectangle, such as a square or a circle. The shape of the substrate 121 or the radiation detection element 122 may also be a shape other than a rectangle, such as a square or a circle. The shape of the block 11 may be any shape other than a truncated pyramid shape, so long as the multiple mounting surfaces 113 are positioned in rotational symmetry around the second through hole 112 and the surface angle between each mounting surface 113 and the bottom surface 115 is an acute angle.

In the first to fifth embodiments, the primary radiation is X-rays, but the radiation detection device 10 may be configured to use radiation other than X-rays as the primary radiation. In this configuration, the radiation detection device 10 includes a radiation source other than the X-ray source 21. For example, the radiation detection device 10 may be configured to use a particle beam such as an electron beam as the primary radiation, and detect secondary radiation generated from the sample 4 by irradiation with the primary radiation, or radiation reflected from the surface of the sample 4.

The radiation detection device 10 may have a form other than the form in which the opening at one end of the second through hole 112 is located at the center of gravity of the bottom surface 115 and the opening at the other end is located at the center of gravity of the top surface 111. The opening at one end of the second through hole 112 may be located at a position other than the center of gravity in the bottom surface 115, and the opening at one end of the second through hole 112 may be located at a position other than the center of gravity of the top surface 111. The radiation detection device 10 may have a form in which the radiation detection module 1 has a plurality of second through holes 112. Alternatively, the radiation detection module 1 may have no second through holes 112. For example, the radiation detection device 10 may be configured to irradiate the sample 4 with primary radiation such as X-rays from the back side of the sample 4 and detect secondary radiation generated from the sample 4 by the irradiation of the primary radiation, or radiation that has passed through the sample 4.

The radiation detection device 10 may be in a form that does not include a radiation source such as the X-ray source 21, the analysis unit 33, or the display unit 34. In a form that does not include the analysis unit 33, the radiation detection device 10 outputs data corresponding to the detection of radiation to the outside, and analysis based on the data is performed externally. In a form that does not include a radiation source, the radiation detection device 10 detects radiation generated externally. Even in this form, it is possible to bring the multiple radiation detection elements 122 closer to the radiation source than before, improving the efficiency of radiation detection.

The present invention is not limited to the contents of the above-described embodiment, and various modifications are possible within the scope of the claims. In other words, embodiments obtained by combining technical means that are appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

REFERENCE SIGNS LIST 1 Radiation detection module 10 Radiation detection device 11 Block 111 Top surface 112 Second through hole 113 Mounting surface (first surface)
114 First through hole 115 Bottom surface (second surface)
116 Opening 117 Electron trap (magnetic field generating mechanism)
12 Radiation detector 121 Substrate 122 Radiation detection element 123 Sensitive area 124 Insensitive area 125 Incident surface 21 X-ray source 22 X-ray optical element 23 Sample stage 4 Sample

Claims (12)

Blocks and
a plurality of radiation detection elements attached to the block;
The block is
a plurality of first surfaces to which the radiation detection elements are respectively attached;
Each of the first surfaces has an opening at one end, and the first surfaces have a plurality of first through holes for passing radiation therethrough;
The radiation detection element has an incident surface onto which radiation is incident,
the radiation detection element is attached to the first surface with the incident surface facing the first surface and with an opening of the first through hole in the first surface being blocked;
the block further has a single second surface different from the plurality of first surfaces;
the other ends of the plurality of first through holes are open to the second surface;
A radiation detection module comprising: 2. The radiation detection module according to claim 1 , wherein a straight line perpendicular to each of the plurality of first surfaces intersects the second surface non-perpendicularly. the plurality of first through holes are linear;
The radiation detection module according to claim 1 or 2 , wherein extensions of central axes of the first through holes intersect with each other at a position in front of the second surface. the block further includes a second through hole having one end open on the second surface and configured to pass radiation to be irradiated onto an external sample disposed opposite the second surface;
The second through hole is linear,
The radiation detection module according to claim 3 , wherein an extension line of central axes of the plurality of first through holes and an extension line of central axes of the second through holes intersect at one point. 4. The radiation detection module according to claim 1, wherein the block has one end open to the second surface and further has a second through hole for passing radiation to be irradiated to an external sample arranged opposite the second surface. openings of the plurality of first through holes in the second surface are located at positions rotationally symmetrical about a center of the second through hole in the second surface,
The radiation detection module according to claim 4 or 5 , wherein the first through holes have the same length. the first surfaces are located at positions rotationally symmetrical about the second through hole,
7. The radiation detection module according to claim 4 , wherein the surface angles between the plurality of first surfaces and the second surface are the same acute angle. The block has a shape in which each of a plurality of side surfaces of a truncated pyramid is enlarged,
the first surface is an enlarged side surface,
The radiation detection module according to claim 7 , wherein the second surface is a lower base surface of the truncated pyramid. the entrance surface includes a sensitive area capable of detecting radiation;
a size of an opening of the first through hole in the first surface is equal to or smaller than a size of the sensitive area,
The radiation detection module according to claim 1 , wherein the radiation detection element is attached to the first surface with the sensitive region covering the opening. the material of the block is ferromagnetic;
10. The radiation detection module according to claim 1, wherein a magnetic field generating mechanism is provided on an inner surface of the first through hole. an irradiation unit that irradiates radiation onto the sample;
The radiation detection module according to claim 1 , further comprising a radiation detection element for detecting radiation generated from the sample;
and a spectrum generating unit that generates a spectrum of the radiation detected by the radiation detection element. an irradiation unit that irradiates radiation onto the sample;
The radiation detection module according to claim 1 , further comprising a radiation detection element for detecting radiation generated from the sample;
a spectrum generating unit that generates a spectrum of the radiation detected by the radiation detection element;
an analysis unit that performs an analysis on the sample based on the spectrum;
a display unit that displays the spectrum generated by the spectrum generating unit or the analysis result by the analyzing unit.

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