JP2008039500A - Radiation detector and radiation analyzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase a quantity of detected radiation reaching a radiation detector in comparison with a conventional constitution. <P>SOLUTION: A radiation analyzer is provided with: the radiation detector 1 for detecting the radiation; optical members 11, 12 having a transmitting function for transmitting the radiation to a radiation guide system into which the detected radiation enters; and a capillary 7 having a focusing function for focusing the radiation entering from the entrance side on the nearest region relative to the radiation guide system on the entrance side. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a radiation detection apparatus that detects radiation with a radiation detector, and a radiation analysis apparatus equipped with the radiation detection apparatus.

  X-ray detection using X-ray detectors / radiation detectors such as TES (Transition Edge Sensor) and STJ (Superconducting Tunnel Junction) as highly sensitive radiation detection X-ray analyzers and radiation analyzers that detect and analyze radiation such as fluorescent X-rays and characteristic X-rays generated when a sample is irradiated with an electron beam or X-ray using an apparatus or radiation detector Is expected. Detectors such as TES and STJ have high energy resolution, so light element K-line and heavy element L-line, which were impossible with conventional detectors, can be separated, and elemental analysis is possible in a low energy band. Is possible.

  In the radiation detectors described above, it is necessary to maintain the surroundings in a predetermined environment (temperature, pressure, etc.) in order to demonstrate the performance of the radiation detector, or the sample such as the measurement object is in a specific state (measurement). It is necessary to set the environment (temperature, pressure, etc.) different from the surroundings of the radiation detector.

  In the radiation detection apparatus using the superconducting tunnel coupling, it is necessary to use the STJ element after cooling it to a temperature of 1K or lower in order to sufficiently maintain the performance of the STJ element serving as the radiation detector. Further, it is known that a semiconductor radiation detector for measuring X-rays or gamma rays serving as a radiation detector is used after being cooled to about 100K.

The radiation detector using STJ is surrounded by the inner radiant heat shield wall and the outer radiant heat shield wall (barrier), and the inner radiant heat shield wall formed by these shield walls is cooled using liquid helium. The outer radiant heat shielding wall is cooled with liquid nitrogen. A window portion is provided in an overlapping portion between a path through which radiation passes between the radiation detector and the sample and the shielding wall, and a window made of beryllium and a radiation heat shielding film are arranged. (For example, see Patent Document 1)
FIG. 2 shows a schematic configuration diagram of an X-ray analyzer using a superconducting transition edge temperature detector (TES) as a radiation detector. The radiation detector 1 using TES is fixed to the tip of the cooling head 2 and inserted into a sample chamber 17 that is kept in a vacuum environment at room temperature. Similarly, an electron column that becomes a radiation source 14 for emitting an electron beam is also inserted into the sample chamber 17. Then, the characteristic X-ray B generated from the sample S by the irradiation of the electron beam A emitted from the lens barrel is detected by the superconducting X-ray detector 20. Here, the superconducting X-ray detector 20 needs to be installed close to the sample S in order to improve the detection efficiency of characteristic X-rays.

  In the vicinity of the sample S, a sample stage 50 for installing the sample, a secondary electron detector 15 for detecting secondary electrons generated from the sample S, and the like are installed.

  The radiation detection apparatus 20 is provided with a refrigerator 40 using a dilution refrigerator in the outer layer 41 provided with a vacuum heat insulating structure in order to cool to about 100 mK in the TES serving as a radiation detector, and is cooled by being connected to the refrigerator. The cooling head 2 is provided in the outer snout layer 3 connected to the outer layer 41 and constructed in a vacuum heat insulating structure, and the radiation detector 1 is fixed to the tip of the cooling head.

  By inserting the snout outer layer 3 from the port of the sample chamber 17, the sample S and the superconducting X-ray detector are installed close to each other. Further, a low-temperature first-stage amplifier for detecting and amplifying the output from the TES serving as the superconducting X-ray detector serving as the radiation detector 1 is fixed to the tip of the cooling head 2, and the superconducting X-ray detector is disposed thereon. It is the structure which mounts | wears.

  FIG. 3 shows a schematic configuration diagram of a tip portion including a radiation detector of an X-ray detection apparatus using a superconducting transition edge temperature detector (TES) as a radiation detector.

  The tip portion mainly has a snout outer layer 3 which is kept in vacuum for heat insulation from the outside, an inner radiant heat shield wall 5 and an outer radiant heat shield wall which are composed of two layers for shielding radiant heat inside the snout outer layer 3. 4, and the radiation detector 1 is mounted via a sensor holder 8 fixed to the tip portion of the cooling head 2 cooled by the refrigerator 40.

  The snout outer layer 3, the inner radiant heat shield wall 5, and the outer radiant heat shield wall 4 are thick and need an appropriate interval. For example, even if the diameter of the snout outer layer is about φ30 mm, the diameter of the cooling head is about φ10 mm. Small diameter.

  A low-temperature first-stage amplifier 6 using a superconducting quantum interferometer (SQUID) is used to amplify an output signal from a superconducting X-ray detector using a TES serving as a radiation detector 1. It is attached to the nearby side with screws.

Further, in order to provide a path for allowing radiation such as X-rays to enter the radiation detector from the outside of the radiation detection device, a window portion is provided in the snout outer layer 3, the inner radiant heat shield wall 5, and the outer radiant heat shield wall 4, It was necessary to provide an optical member that transmits X-rays in the window. (For example, see Patent Document 2.)
Japanese Patent Laid-Open No. 7-253472 Japanese Patent Laid-Open No. 17-214792

  However, the following problems remain in the conventional radiation detection apparatus and the radiation analysis apparatus using the same.

  In other words, the provision of the optical member that transmits X-rays requires that the radiation detector be kept at a low temperature, so that intrusion of radiant heat from the outside of the radiation detection device is suppressed, and further, the radiation detection device outside and the radiation detection device inside This is because it is necessary to maintain this pressure difference in an environment where the pressure is different on the radiation detector side.

  However, since this optical member is provided, there is a problem in that the intensity of the radiation entering the radiation detector, particularly in the low energy band, is smaller than when no optical member is provided. Furthermore, the thickness of the optical member provided in the window portion of the outer layer of the snout increases in order to maintain a pressure difference from the outside of the radiation detection device, so that the radiation that absorbs more radiation and can enter the radiation detector is reduced. End up.

  The present invention has been made in view of the above matters, and can increase the intensity of radiation incident on the radiation detector from the outside of the radiation detection device while maintaining a pressure difference between the outside of the radiation detection device and the inside of the radiation detection device. It is an object to provide a radiation detection apparatus.

  It is another object of the present invention to provide a radiation analyzer on which such a radiation detection apparatus is mounted.

  The present invention provides the following means in order to solve the above problems.

The radiation detection apparatus according to the present invention includes a radiation detector and a system in which a sample is arranged and radiation is detected, and the radiation generated by the sample by the radiation applied to the sample is detected by the radiation detector. A barrier is provided to keep the system different from the existing system. Among the overlapping portions of the radiation waveguide system and the barrier from the sample to the radiation detector, on the radiation waveguide system, the portion closest to the sample or in the vicinity of the portion (2-1) to (2-3) It is comprised with the member (condensing member) which has a function. That is, this part (through hole (window part, X-ray transmission window) provided in the barrier) is configured to substantially have the following functions (2-1) to (2-3).
(2-1) Transmission function: A function of transmitting radiation used for detection by the radiation detector.
(2-2) Condensing function: A function of condensing this radiation incident from the sample side.
(2-3) Shielding function: A function that is preferably equivalent to or higher than the function of the barrier in which the above-described part exists, and at least the same function.

  In this specification, “radiation” refers to material particles (particle beams such as ions, electrons, neutrons, protons, and mesons) that flow with kinetic energy, such as γ-rays, X-rays, visible light, and infrared rays. It refers to electromagnetic waves.

  “System” in the terms “system where sample is placed and radiation is incident” and “system where radiation detector is placed” refers to the surrounding state, environment and atmosphere where the sample is placed. Say. There are a case where the state where the sample is arranged must be regulated as a measurement condition, a case where the state where the radiation detector is arranged must be regulated, and a case where both are restricted.

  The “state” to be regulated includes, for example, a temperature, a degree of vacuum, a magnetic field condition, and the like, and is set as appropriate. The two systems are separated by one or more barriers. For example, the radiation detector is surrounded by one or more barriers, and each system (space) formed by the barriers is in an optimal state in order to enable the radiation detector to operate or to operate well. Sometimes. More specifically, taking a superconducting X-ray detector as an example, the superconducting X-ray detector, which is a radiation detector, is the most external in order to bring the superconducting X-ray detector to a temperature of about 100 mK (substantially operable temperature). The temperature may be set so that the temperature decreases in order from the inner system to the inner system in order from the system to the inner system.

  In this specification, “system state” and the like are appropriately described. For example, the barrier is cooled or liquid nitrogen or liquid helium is circulated in the barrier, and as a result, “system state” is obtained. Of course, the above concept also includes control of the above. That is, both the concept of primary control of the “system” itself and the concept of secondary control (regulation) using other members and the like are included.

  A “radiation waveguide system” is a path through which radiation emitted from a sample, particularly detection radiation, reaches a radiation detector, and is generally referred to as an optical path when light is used as detection radiation. The radiation waveguide system may connect the radiation detector from the sample at the shortest distance, but is not limited thereto.

  In the part that overlaps the barrier in the radiation waveguide system, there is a “window” in the barrier so that at least the detection radiation used by the radiation detector is transmitted from the sample side to the radiation detector side on the radiation waveguide system. Provided. The “window” may be a part where nothing is provided depending on the design, but generally, at least a transmission function that transmits the radiation for detection, a system on the sample side of the barrier in which this window exists, and a radiation detector An optical member having a shielding function for shielding the side system is substantially disposed. In the detection apparatus, the window portion closest to the sample on the radiation waveguide system further has a light collecting function. In addition, as described above, the light collecting member and the optical member may be any one that realizes each function in the window portion in which the light collecting member and the optical member are disposed, and these members need to be fitted to the window portion. Absent.

  The “condensing” function is a function of collecting (focusing) incident radiation on the emission side. In the detection apparatus, the light condensing member condenses at least detection radiation. It should be noted that “light collection” in this specification is not limited to the meaning of collecting light.

Since the detection device is configured as described above, the following effects are exhibited.
(3-1) The amount of detection radiation reaching the radiation detector is larger than that of a conventional detection device having a solid angle equivalent to that of the detection device.

In order to obtain a solid angle equivalent to that of the above-described detection apparatus with a conventional detection apparatus, a member having a condensing function and a transmission function must be arranged further on the sample side of the window part on the most sample side on the radiation waveguide system. I must. Therefore, in the conventional detection device, the number of elements that absorb / attenuate radiation is increased by the amount of this member as compared with the detection device. Therefore, the detection device intensifies the detection radiation incident on the radiation detector, particularly in a low energy region that is easily absorbed / attenuated, as compared with a conventional detection device having an equivalent solid angle (having a light collecting performance). It becomes possible.
(3-2) It is easy to increase the amount of radiation reaching the radiation detector as compared with a conventional detection device having the same number of optical members (in this section, the optical member includes a condensing member).

  The conventional detection device in this comparison includes the same number of optical members as the number of optical members included in the detection device. That is, the detection device is configured by replacing the optical member closest to the sample on the radiation waveguide system with the light collection member as compared with the conventional detection device. Therefore, the optical member on the most sample side on the radiation waveguide system can increase the amount of incident detection radiation in the detection device than in the conventional detection device. This is because the light collecting member has a light collecting function. Therefore, it is easy to increase the intensity of the detection radiation that reaches the radiation detector, particularly in the low energy region that is easily absorbed / attenuated, compared to the conventional one.

In particular, when the optical member on the most sample side is provided with pressure resistance and hermeticity for the function of shielding (one aspect of the shielding function described in (2-3) above), the transmission function of these members is: In general, it becomes extremely worse especially for radiation in the low energy region. For example, when an optical member for maintaining a vacuum degree of about 10 ⁻⁶ Pa is used on the inner side of the optical member on the most sample side when the sample side is at atmospheric pressure, this optical member, and in particular, the detection device has a particularly low energy. The transmission performance for the detection radiation in the band is extremely deteriorated, and it is extremely difficult to reach the superconducting X-ray detector with a sufficient amount of characteristic X-rays (detection radiation) for detection and analysis. The present inventors have found out. For this reason, there is a possibility that the detection efficiency is deteriorated, the elemental analysis takes an extremely long time, or the statistical error is large and a clean energy spectrum cannot be obtained. On the other hand, the above detection apparatus has a shielding function having a pressure resistance of a degree of vacuum, but since a member having a condensing function is arranged on the most sample side, the conventional detection apparatus As a result, it is possible to increase the amount of detection radiation that passes to the radiation detector side. Therefore, it is possible to avoid the above problems.

As described above, the detection device can increase the amount of detection radiation incident on the radiation detector as compared with the conventional detection device. In addition, depending on the environment required for the system in which the radiation detection device is arranged and / or the system in which the sample is arranged, detection by the conventional detection device is substantially difficult. The present inventors have found that the above can be realized.
(3-3) The degree of freedom of the detection target is increased as compared with a conventional detection apparatus in which the detection radiation incident on the radiation detector is equivalent.

  The conventional detection device in which the amount of detection radiation incident on the radiation detector is equivalent to that of the detection device has a limited shielding function that can be provided on the window and thus the barrier, compared to the detection device, A configuration in which the optical member is not disposed in one or more of the window portions is unavoidable. As in the example described in (3-2) above, the optical member has a shielding function, the radiation detector is substantially operated, and / or the atmosphere of the sample is set to a predetermined measurement condition. This is because, in most cases, the performance of the transmission function must be sacrificed if the performance is set so as to exhibit the performance.

  For example, if a superconducting X-ray detection device having a radiation incident amount equivalent to the above detection device (the amount of radiation reaching the radiation detector) is configured as a conventional detection device, the environmental conditions of the system in which the sample is arranged are limited. Will be. This is because the conventional detection apparatus needs to eliminate one or a plurality of optical members on the most sample side in order to obtain the transmission performance equivalent to that of the detection apparatus. In this configuration, the degree of vacuum on the radiation detector side is the same as the system on which the sample is placed. Therefore, if the degree of vacuum on the system on which the sample is placed is close to atmospheric pressure, the degree of vacuum on the radiation detector side also increases. As a result, the effect as a vacuum heat insulating layer for a refrigerator or the like is reduced, and the radiation detector is not sufficiently cooled and substantially does not operate. Alternatively, since the pressure of the system in which the sample is arranged is lowered by exhausting the vacuum heat insulating layer on the radiation detector side, for example, analysis of a biological sample or an insulator becomes substantially impossible.

  The detection device may include a mechanism that relatively moves the light collecting member in at least a one-dimensional direction. That is, this mechanism is a mechanism (adjustment mechanism) that adjusts the waveguide of the radiation waveguide system by moving the condensing member. By providing the adjustment mechanism, it is possible to select and produce an optimum path as the radiation waveguide system. Relative movement refers to changing the relative position of the light condensing member in the detection device. In general, the point that intersects the most existing window on the straight line connecting the sample and the radiation detector is used as a reference. Or to be able to move in a substantially vertical direction (two-dimensional direction) with respect to the straight line.

  When the adjustment mechanism is provided, if the incident direction of radiation to the light collecting member is approximated by a straight line, it is extremely possible to move the light collecting member in a plane direction perpendicular to the straight line, that is, in a two-dimensional direction. Good. This is because the traveling direction of the detection radiation emitted from the light collecting member can be controlled. That is, the amount of detection radiation incident on the radiation detector can be adjusted. However, the amount of radiation reaching the radiation detector can be greatly increased if the linear direction can be adjusted, or if the condensing member can be rotated in another direction. It is desirable because it becomes possible.

  In the case where an adjustment mechanism is provided in the detection apparatus and the state is controlled so that the degree of vacuum is different between the system in which the sample is arranged and the system present on the radiation detector side than this system, Furthermore, it is preferable to provide a sealing member. The sealing member is a member whose shape can be changed in accordance with the movement of the light collecting member. For example, a member having a variable shape such as bellows or rubber and having sufficient sealing performance is employed. The sealing member is disposed and connected so as to seal a portion of the light collecting member that is moved by the adjustment mechanism.

  The detection apparatus as described above is particularly optimal as a superconducting radiation detection apparatus such as a superconducting X-ray detection apparatus.

  A superconducting radiation detection device refers to a detection device in which a radiation detector (particularly a portion that substantially detects radiation) is configured using a superconducting element. That is, in the above detection apparatus, the radiation detector is a superconducting radiation detector, and the system in which the superconducting radiation detector is arranged refers to an apparatus in which an environment (temperature) in which the radiation detector can operate is set. Of course, in order to create this system environment, various known techniques are used, and other system environments are also set as appropriate. For example, a mode in which an appropriate refrigerant is circulated through one or more barriers is also included.

  Superconducting radiation detection devices require that the radiation detector be placed at a very low temperature. In order to obtain a system that achieves this temperature condition, the detection device needs to be provided with a plurality of barriers. Therefore, for the same reason as described above, the present inventors have found that it is extremely difficult to reach a sufficient amount of detection radiation to the radiation detector when the configuration of the conventional detection apparatus is employed. On the other hand, the present inventors have found that if the configuration of the above-described detection apparatus is adopted, it becomes easy to reach a radiation detector with a sufficient amount of detection radiation for detection.

The analyzer according to the present invention detects, with a radiation detector, radiation generated in the sample due to radiation irradiated on the sample, radiation reflected on the sample, or both (radiation for detection). An apparatus for analyzing the state of a sample, comprising the following configuration.
-Radiation irradiation member: A member that irradiates a sample with radiation.
Sample holder: A member that holds a sample in a predetermined position.
-The detection device described above.

The operation of the analyzer is as follows.
(4-1) Radiation is emitted from the radiation irradiating member.
(4-2) This radiation is incident on the sample.
(4-3) The radiation is reflected by the sample. And / or other radiation (secondary radiation) is emitted from the sample due to the radiation. That is, radiation including detection radiation is emitted from the sample.
(4-4) At least detection radiation is incident on the detection device.
(4-5) The detection device detects the incident radiation and outputs the detection result.

  Since the analysis device includes the detection device, the above-described operation can be obtained for the detection device. That is, it is possible to obtain a detection result (analysis result) better than that of the conventional analyzer, or a detection result that could not be substantially obtained by the conventional detector.

  According to the radiation detection apparatus and the radiation analysis apparatus according to the present invention, the intensity of radiation incident on the radiation detector from the outside of the radiation detection apparatus can be increased while maintaining a pressure difference between the outside of the radiation detection apparatus and the inside of the radiation detection apparatus. . As a result, radiation such as minute X-rays can be measured with high precision, and radiation such as characteristic X-rays and fluorescent X-rays emitted from the specimen is irradiated with the radiation. By using the detection device, the sample can be analyzed with high accuracy.

  Hereinafter, a radiation detection apparatus and a radiation analysis apparatus according to embodiments of the present invention will be described in more detail using examples applied to a superconducting X-ray detection apparatus and a superconducting X-ray analysis apparatus.

  FIG. 1 is a cross-sectional view schematically showing a configuration of a radiation detection apparatus according to an embodiment of the present invention.

  This radiation detector is a cross-sectional view schematically showing a configuration of a region indicated by a broken line of the radiation detection apparatus in the radiation analysis apparatus shown in FIG.

  The basic configuration of the radiation analysis apparatus in this embodiment according to the present invention and the conventional radiation analysis apparatus are the same, and are different in the configuration of the region indicated by the broken line shown in FIG. The same components as those described in 2 or 3 are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 1 shows a schematic configuration diagram of a tip portion including a radiation detector of an X-ray detection apparatus using a superconducting transition edge temperature detector (TES) as a radiation detector.

  The tip portion mainly has a snout outer layer 3 which is kept in a vacuum for heat insulation from the outside, an inner radiant heat shielding wall 5 and an outer radiant heat shielding wall which are composed of two layers for blocking radiant heat inside the snout outer layer 3. 4, and the radiation detector 1 is mounted via a sensor holder 8 fixed to the tip portion of the cooling head 2 cooled by the refrigerator 40.

  A SQUID using a plurality of superconducting quantum interferometers (SQUIDs) to process the output signal from a superconducting X-ray detector using a superconducting transition edge temperature detector (TES) as the radiation detector 1 The low-temperature first-stage amplifier 6 serving as an amplifier is attached to the side surface near the tip of the cooling head 2 by screws.

  Further, in order to provide a path for allowing radiation such as X-rays to enter the radiation detector from the outside of the radiation detection apparatus, windows are provided in the outer snout layer 3, the inner radiant heat shield wall 5, and the outer radiant heat shield wall 4. Yes.

  In the present embodiment, the snout outer layer 3 has a vacuum heat insulating structure as heat insulation, and by using a vacuum pump (not shown) to make a vacuum state (for example, about 10 −6 Pa), heat from the outside can be obtained. The inside of the radiation detector is insulated.

  The outer radiant heat shield wall 4 and the inner radiant heat shield wall 5 have a structure capable of injecting liquid, and liquid nitrogen is injected into the outer radiant heat shield wall 4 and liquid helium is injected into the inner radiant heat shield wall 5. It was made to cool with. Thereby, the superconducting X-ray detector using the superconducting transition edge temperature detector (TES) as the radiation detector 1 is cooled to about 100 mK and can be held at the superconducting transition edge to drive the TES. become.

  The sensor holder 8 is made of high-purity oxygen-free copper having good heat conduction characteristics, but may be manufactured using other materials having such characteristics, such as sapphire.

  The inner radiant heat shield wall 5 and the outer radiant heat shield wall 4 are each provided with an X-ray transmission window (window) having a diameter of 5 mm so that X-rays emitted from the sample are incident on the radiation detector 1. . These X-ray transmission windows (window portions) have a heat insulation function preferably equal to that of each shielding wall, and at least the radiation detector 1 among the X-rays emitted from the sample S. Optical members 11 and 12 having a transmission function of transmitting components (X-rays) used for detection. In this embodiment, an aluminum mylar is used.

  The optical members 11 and 12 may be provided so as to be positioned in the window as in the present embodiment, but are not limited to this configuration and arrangement as long as at least the above two functions can be realized. In other words, the X-rays pass through the window part, and the structure in which the penetration of radiant heat from the high temperature side system to the low temperature side system does not substantially occur through the window part, The configuration described above can be employed as appropriate.

  The snout outer layer 3 is provided with an X-ray transmission window which is a through hole having a diameter of 5 mm in a region overlapping with the X-ray waveguide. On the sample S side of the X-ray transmission window, a light collecting member including the capillary 7 and the capillary holding portion 21 as main components is provided. One end of the capillary holding part 21 is fixed in contact with the outer snout layer 3. The capillary holding unit 21 is configured to hold the capillary 7 so that the capillary 7 is closer to the sample S than the X-ray transmission window and the axes of the capillary 7 and the X-ray transmission window substantially coincide. The X-ray transmission window has a structure shielded from the system on the sample S side by the capillary 7 and the capillary holder 21.

  The capillary holding part 21 formed a vacuum heat insulating structure using a material equivalent to the material constituting the snout outer layer 3. Thus, the heat insulating function equivalent to that of the snout outer layer 3 was provided.

  As described above, the capillary 7 is arranged substantially coaxially with the X-ray transmission window. In this embodiment, a 10 mm diameter flexible tube was used. In this embodiment, the capillary 7 employs an X-ray condenser lens in which a plurality of glass tubes having a structure that totally reflects X-rays are bundled so as to focus on one point or a partial region of the radiation detector 1. Since such a configuration / arrangement is employed, the capillary has a condensing function and a transmission function for X-rays.

Since the capillary 7 bundles the thin glass tubes as described above, the conductance with respect to the passage of the gas can be very small. In this example, a pressure difference of 10 ² Pa or more could be maintained between the radiation detector 1 side and the sample S side. In other words, the pressure shielding function was also realized.

  As described above, the light collecting member realizes a heat and pressure shielding function and a specific X-ray transmission function without providing an optical member in the X-ray transmission window, and further realizes a specific X-ray light collecting function. . That is, a hermetic structure that maintains the degree of vacuum and the degree of cooling of the radiation detector 1 of the radiation detection apparatus and its surroundings without changing from the conventional one is realized, and the cooling of the radiation detector 1 by the refrigeration apparatus 40 is achieved. It was possible. As a result, the amount of X-rays incident on the radiation detector 1 can be made much larger than before.

  In this example, sealing was performed in order to further enhance the pressure shielding function of the light collecting member. The seal mainly comprises the bellows 22 and the O-rings 24 and 25. The O-ring 25 covers the capillary 7, and the O-ring 24 is provided so as to cover the inner side / inner wall of the capillary holding part 21 (preferably near the junction between the capillary holding part and the snout outer layer 3). The bellows 22 is placed on the inner wall of the capillary holding portion 21 between the O-rings 24 and 25.

  In the present embodiment, an adjusting mechanism for adjusting the optical axis of the condensing member (more specifically, the capillary 7 as a member having a condensing function and a transmission function in the condensing member) is further provided. . The adjusting mechanism is configured to bear a portion (actually holding portion) in contact with the capillary 7 in the capillary holding portion 21, and two axes extending from the outside of the capillary holding portion 21 to the surface of the capillary 7 are not substantially coincident with each other. The optical axis adjusting member 23 is composed of an adjusting screw. By adjusting with the adjusting screw, it becomes possible to move the capillary 7 in a direction substantially perpendicular to the straight line when the position and the optical axis of the capillary 7 are approximated to a straight line of the specific X-ray waveguide. The amount of X-rays to be adjusted can be adjusted.

  The snow part where the radiation detector 1 of the radiation detection apparatus is arranged is configured to be inserted into the sample chamber 17 as shown in FIG. By configuring in this way, the X-ray distance between the radiation detector 1 and the sample S was shortened. Since this structure is adopted, it is possible to increase the solid angle for the radiation detector 1 as compared with the case where the distance between the tip of the capillary 7 and the sample S is longer. Further, the attenuation of X-rays from the sample S to the radiation detector 1 can be further reduced.

  The radiation detector 1 was mounted on the sensor holder 8 with an adhesive such as varnish using a superconducting transition edge temperature detector (TES). The sensor holder 8 is made of oxygen-free copper, but when controlling the temperature condition of the radiation detector as in this embodiment, in addition to this material, the thermal conductivity of sapphire or the like. It can be appropriately prepared by a known method using a material having a high thickness.

  The low-temperature first-stage amplifier 6 was mounted on the amplifier holder 31 fixed to the cooling head 2 with an adhesive. The amplifier holder 31 is attached to the side surface near the tip of the cooling head 2 with screws. The low-temperature first-stage amplifier 6 uses an SQUID array in which 250 superconducting quantum interference devices (SQUIDs) are connected in series.

  The radiation detector 1 and the low-temperature first-stage amplifier 6 were connected by aluminum (Al) wire bonding 10. The wiring for driving the radiation detector 1 was electrically connected to a connector (not shown) attached to the exterior 41 of the radiation detector 20 via a lead wire.

  The low-temperature first-stage amplifier 6 and a normal temperature side control device (not shown) were connected by wiring 9. The electrode for driving the low-temperature first-stage amplifier 6 was electrically connected to a connector (not shown) attached to the exterior 41 of the radiation detection apparatus 20 by wiring 9.

  In this embodiment, the wiring 9 is made of a copper wire having high conductivity. However, at least a part of the room temperature side of the cooling head is a superconducting niobium titanium wire, manganin wire, stainless steel wire or the like. When used, it is preferable because it can prevent heat penetration from room temperature and improve detection performance.

For the wirings and circuits not described above, the same configuration as that employed in a known superconducting X-ray detection apparatus was appropriately adopted.
<Action>
The superconducting X-ray analyzer and superconducting X-ray detector according to the present embodiment operate as follows to realize elemental analysis of a sample.
(5-1) About the radiation detection apparatus 20, the outer layer 41 and the inside of a snout are evacuated and liquid nitrogen is injected into the outer radiant heat shield wall 4 and liquid helium is injected into the inner radiant heat shield wall 5 to be cooled.
(5-2) The inside of the sample chamber 17 and the electron column that becomes the radiation source 14 for emitting the electron beam are evacuated.
(5-3) The sample S fixed to the sample stage 16 is irradiated from the electron column while searching for the electron beam. The secondary electrons emitted from the sample S are image-observed by a secondary electron detector, and the region of the sample S to be observed is specified.
(5-4) While irradiating the measurement region on the sample S with the electron beam, the characteristic X-rays emitted from the sample S pass through the capillary 7 and the optical members 11 and 12 of the radiation detection device 20 and enter the radiation detector 1. Incident.
(5-5) The characteristic X-ray incident on the radiation detector 1 is converted into an electric signal by the radiation detector 1, and then this signal is amplified by an amplifier (not shown) and a waveform shaper (not shown). ) Etc., and energy analysis is performed with a wave height analyzer. Thereby, the elemental analysis of the sample S can be performed.
<Modification>
The superconducting X-ray detection apparatus and superconducting X-ray analysis apparatus according to the above-described embodiment are the detection performance superior to the conventional superconducting X-ray detection apparatus and superconducting X-ray analysis apparatus as a result of the present inventors' implementation. However, as described above, the detection device / analysis device according to the present invention can be appropriately modified based on the spirit and the spirit thereof. For example, even if the following modifications are made, excellent performance can be exhibited. In addition, if the modified examples are used in combination as long as they do not contradict each other, extremely good performance can be exhibited.
One or more of the optical members 11 and 12 may further have a light collecting function. With this configuration, it is possible to increase the amount of radiation for detection that passes through the optical member, and it is possible to increase the detection accuracy of the detection device / analyzer and shorten the time required for detection. It becomes.
The adjusting mechanism may be configured by adopting a known member moving mechanism (relative position fine adjusting mechanism) so that it can be moved in a direction different from that according to the above embodiment. When such movement becomes possible, it becomes possible to adjust the amount of the detection radiation incident on the light collecting member with a higher degree of freedom. As a result, adjustment such as increasing the amount of radiation for detection that passes through the optical member increases the degree of freedom. For example, the detection accuracy of the detection device / analyzer can be increased, or the time required for detection can be shortened. It becomes possible.
-Although the superconducting X-ray analyzer which concerns on the said Example used the electron column as a scanning electron microscope (SEM) as a radiation source, it is not limited to this. For example, an X-ray source may be used as a radiation source to irradiate the sample with X-rays and analyze the fluorescent X-rays emitted from the sample. That is, the radiation source only needs to be capable of irradiating the sample with radiation necessary for measurement.

It is a block diagram for demonstrating schematic structure of a radiation analyzer. It is an enlarged view for demonstrating a structure and arrangement | positioning, such as a radiation detector and a capillary of the radiation detection apparatus in a present Example. It is an enlarged view for demonstrating a structure and arrangement | positioning, such as a radiation detector of a conventional radiation detection apparatus, and an optical member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Radiation detector 2 Cooling head 3 Snout outer layer 4 Outer radiation heat shielding wall 5 Inner radiation heat shielding wall 6 Low temperature first stage amplifier 7 Capillary 8 Sensor holder 9 Wiring 10 Wiring 11 and 12 Optical member 13 Optical member 13 Radiation source 15 Secondary electron detection 16 Sample stage 17 Sample room

20 radiation detector 21 capillary holding part 22 bellows 23 optical axis adjusting member 24, 25 O-ring 30 scanning electron microscope 40 cooler 41 outer layer

Claims (6)

A radiation detector for detecting radiation;
A radiation waveguide system for directing radiation to the radiation detector;
One or a plurality of barriers separating a system on which radiation of the radiation waveguide system is incident and a system on which the radiation detector is disposed;
The barrier is
An optical member having a portion that overlaps with the radiation waveguide system has at least a transmission function that transmits radiation detected by the radiation detector and a shielding function that partitions the system inside and outside the barrier,
Among the parts that overlap with the radiation waveguide system, in the part that is closest to the radiation incident side on the radiation waveguide system, an optical member is used, and radiation that is incident from the side on which the radiation is incident. A radiation detection apparatus configured as a condensing member having a condensing function for condensing light.   The radiation detection apparatus according to claim 1, further comprising an adjustment mechanism for adjusting the radiation waveguide system by relatively moving the light collecting member in at least a one-dimensional direction.   The radiation detecting apparatus according to claim 1, wherein the condensing member has a structure in which glass capillaries that reflect the radiation are bundled. The radiation detection apparatus according to claim 2,
The system on the radiation incident side and the system adjacent to the radiation detector side with respect to the system are controlled so that at least the degree of vacuum is different,
A radiation detection apparatus further provided with a sealing member that performs sealing between both systems by changing the shape following the relative movement of the light collecting member. The radiation detection apparatus according to any one of claims 1 to 4,
The radiation detector is a superconducting radiation detector;
The system in which the radiation detector is disposed is a radiation detection apparatus that is a system at a temperature at which the radiation detector can operate. Comprising the radiation detection device according to any one of claims 1 to 5,
An irradiation member for irradiating the sample with radiation or charged particles;
A radiation analyzer using a radiation detection apparatus, comprising: a sample holder that holds a sample; and a radiation detector that detects radiation generated on the sample and / or reflected radiation by radiation or charged particles irradiated on the sample.

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