Semiconductor neutron detection device and method for manufacturing same

Abstract

A semiconductor neutron detection device (10) comprises a neutron detector (11) that generates, in response to incident neutrons, an electric signal that can be output to the outside. The neutron detector (11) includes a polycrystalline compound semiconductor and a neutron capture substance mixed in the compound semiconductor. The neutron capture substance includes a neutron capture element that captures neutrons incident on the neutron detector, and generates radiation or light as a result of the capture. The compound semiconductor generates electron-hole pairs by the radiation or light, and the electric signal is generated by the electron-hole pairs. The neutron detector (11) can be manufactured by heating a powder aggregate containing a base material powder of a compound semiconductor material and an additive powder of a neutron capture substance.

Description

Semiconductor neutron detector and its manufacturing method

[0001] This invention relates to a semiconductor neutron detection device using a compound semiconductor and a method for manufacturing the same. In one example, this semiconductor neutron detection device can be configured as a flat-panel type neutron detector.

[0002] Neutrons can be used in boron neutron capture therapy (BNCT) and non-destructive testing. In BNCT, boron compounds are accumulated in cancer cells, and neutron beams are used to emit radiation (alpha particles and...) from the boron. ７ It selectively destroys cancer cells using Li nuclei. In non-destructive testing, the object to be tested is irradiated with neutron beams, and the presence or absence of defects in the object is checked based on the neutrons emitted from the object as a result (e.g., backscattered neutrons).

[0003] In BNCT, it is necessary to measure the neutron dose at the neutron irradiation site and at various locations near it in order to evaluate and optimize the neutron dose irradiated to cancer cells. In non-destructive testing, for example, it is necessary to measure the number of neutrons from the object being inspected at various locations in order to evaluate the location of defects in the object being inspected. Thus, in BNCT and non-destructive testing, it is necessary to measure the amount of incident neutrons at various locations. For example, there is a need for highly accurate measurement of the spatial distribution of incident neutrons (e.g., real-time measurement).

[0004] Such neutrons have traditionally been, ３ Gas detectors using helium (He) were primarily used.

[0005] Japanese Unexamined Patent Publication No. 61-80084

[0006] Used in neutron detection ３ Due to the shortage of He supply, ３ A neutron detection device that does not use helium (He) is needed. For example, one could consider using a semiconductor neutron detector that has a compound semiconductor epitaxial film in which neutron-capturing elements such as boron are constituent elements.

[0007] However, in this case, it is difficult to increase the concentration of neutron-capturing elements in compound semiconductor epitaxial films, and there is a limit to the concentration. Furthermore, compound semiconductor epitaxial films are formed as thin films (for example, films of a few micrometers to tens of micrometers in thickness) by growing crystals using epitaxial methods such as CVD (Chemical Vapor Deposition), and their thickness may be insufficient when used in neutron detectors. Patent document 1 describes a neutron semiconductor detector fabricated by the CVD method.

[0008] Therefore, the object of the present invention is to enable, or both, to easily increase the concentration of the neutron-capturing element and increase the thickness of the compound semiconductor in a semiconductor neutron detector using a compound semiconductor containing a neutron-capturing element.

[0009] A semiconductor neutron detection device according to one aspect of the present invention comprises a neutron detector that generates an electrical signal that can be output to the outside in response to an incident neutron, wherein the neutron detector comprises a polycrystalline compound semiconductor and a neutron-capturing material mixed within the compound semiconductor, wherein the neutron-capturing material comprises a neutron-capturing element that captures neutrons incident on the neutron detector and generates radiation or light through such capture, and the compound semiconductor generates electron-hole pairs in response to the radiation or light, and the electrical signal is generated by these electron-hole pairs.

[0010] A method according to one aspect of the present invention is a method for manufacturing a semiconductor neutron detector equipped with a neutron detector that generates an electrical signal that can be output externally by incident neutrons, comprising: (S1) preparing a powder assembly by mixing a base material powder of a compound semiconductor material and an added powder of a neutron-capturing substance; (S2) heating the powder assembly to form the neutron detector from the base material powder, the neutron-capturing substance comprising a polycrystalline compound semiconductor and a neutron-capturing substance mixed within the compound semiconductor; the neutron-capturing substance comprising a neutron-capturing element that captures incident neutrons and generates radiation or light by such capture; the compound semiconductor generates electron-hole pairs by the radiation or light, and the electrical signal is generated by these electron-hole pairs.

[0011] According to one aspect of the present invention, in a semiconductor neutron detection device using a compound semiconductor containing a neutron-capturing element, it is possible to easily increase the concentration of the neutron-capturing element and / or increase the thickness of the compound semiconductor.

[0012] This is a schematic cross-sectional view showing the main part of a semiconductor neutron detector according to an embodiment of the present invention. This is a view taken along the line 1B-1B in Figure 1A. This is an explanatory diagram schematically showing a magnified portion of a minute part of the neutron detector in Figure 1A. This shows an example of the configuration of a semiconductor neutron detector. This shows another example of the configuration of a semiconductor neutron detector. This is a flowchart showing a method for manufacturing a semiconductor neutron detector according to an embodiment of the present invention. This shows an example of the configuration of a semiconductor neutron detector configured as a flat panel type. This shows another example of the configuration of a semiconductor neutron detector configured as a flat panel type.

[0013] Embodiments of the present invention will be described based on the drawings. Common parts in each drawing are denoted by the same reference numerals, and redundant explanations are omitted.

[0014] (Configuration of the semiconductor neutron detection device 10) Figure 1A is a schematic cross-sectional view showing the main parts of the semiconductor neutron detection device 10 according to an embodiment of the present invention. Figure 1B is a view taken along the line 1B-1B in Figure 1A. Note that Figure 1A is a cross-sectional view taken along the line 1A-1A in Figure 1B.

[0015] The semiconductor neutron detection device 10 according to this embodiment can be used for any of the following purposes (1) to (4), but may also be used for other purposes. (1) In BNCT, to measure the neutron dose at the irradiation site and various locations near it in order to evaluate and optimize the neutron dose irradiated to cancer cells. (2) In non-destructive testing, to measure the number of neutrons from an object at various locations in order to evaluate the location of defects in the object being inspected. (3) In relation to nuclear security, to detect neutrons near luggage in order to detect nuclear material hidden in luggage at a predetermined location (e.g., transportation-related facilities such as airports). (4) To detect neutrons in order to inspect whether neutrons are leaking at a nuclear facility.

[0016] For purposes such as the above (1) or (2), the semiconductor neutron detector 10 is an apparatus for measuring the amount of neutrons incident on a neutron detector 11 described later (for example, FIG. 3 described later). For purposes such as the above (3) or (4), the semiconductor neutron detector 10 is an apparatus for detecting the presence or absence of neutrons incident on the neutron detector 11 (for example, Modified Example 7).

[0017] As shown in FIG. 1A and FIG. 1B, the semiconductor neutron detector 10 includes a neutron detector 11 and electrodes 12 and 13.

[0018] The neutron detector 11 comprises a polycrystalline compound semiconductor (hereinafter also simply referred to as a compound semiconductor) and a neutron capture substance. The neutron capture substance is mixed in the compound semiconductor. Note that part of the neutron capture substance may be present on the surface of the neutron detector 11.

[0019] The neutron detector 11 may be a sintered body of a compound semiconductor and a neutron capture substance. The neutron detector 11 (compound semiconductor) may contain a flux used in sintering (step S11 described later) or a substance (for example, a compound) derived from the flux.

[0020] The compound semiconductor forms the neutron detector 11 in a polycrystalline state. That is, the neutron detector 11 is a compound semiconductor in which a neutron capture substance is mixed internally. The compound semiconductor may be a single continuous polycrystalline body throughout the entire neutron detector 11. In such a polycrystalline compound semiconductor, for example, a large number of crystal grains of the polycrystal are connected to each other via grain boundaries throughout the entire neutron detector 11, and electrons and holes of electron-hole pairs generated as described later can move between the crystal grains through the respective grain boundaries.

[0021] FIG. 2 is an enlarged schematic view showing a minute part (cubic portion) of the neutron detector 11 in FIG. 1A. In FIG. 2, reference symbol R1 indicates a continuous region of the polycrystalline compound semiconductor, and reference symbol R2 indicates a fine region of the neutron capture substance.

[0022] The dimensions, shapes, densities, and other properties of each fine region R2 of the neutron capturing material shown in FIG. 2 are not necessarily accurate. That is, the actual dimensions, shapes, densities, and other properties of the fine regions R2 of the neutron capturing material may differ from those shown in FIG. 2. As shown in FIG. 2, a large number of fine regions R2 of the neutron capturing material are dispersed and exist within the continuous region R1 of the compound semiconductor. That is, as shown in FIG. 2, the region other than the fine regions R2 is the region R1 of a polycrystalline compound semiconductor that is continuous throughout.

[0023] As the large number of fine regions R2, the neutron capturing material may be dispersed and mixed in the compound semiconductor (for example, substantially uniformly). The large number of fine regions R2 may exist, for example, as a large number of particles. The large number of fine regions R2 may be in a crystalline state or an amorphous state.

[0024] The dimension of each fine region R2 may be on the order of micrometers, for example, less than 5 μm, less than 3 μm, or less than 1 μm. In the present specification, the dimension of the fine region R2 may be the maximum dimension among dimensions in all directions of the fine region R2 (particle R2) (the same applies hereinafter). Alternatively, when the fine region R2 is formed as a particle, the average particle diameter of the fine region R2 may be on the order of micrometers, for example, less than 5 μm, less than 3 μm, or less than 1 μm. In the present specification, the average particle diameter (diameter) may be expressed as an equivalent circle diameter measured by microscopy, or expressed as an equivalent sphere diameter measured by light scattering method (the same applies hereinafter). Furthermore, the average particle diameter may refer to the particle diameter at 50% cumulative value in the particle size distribution representing the measurement results when the particle diameter of each particle is measured by microscopy or light scattering method (the same applies hereinafter).

[0025] The neutron-capturing material is, for example, a compound or element in which a neutron-capturing element is a constituent element. In this embodiment, the neutron-capturing element captures neutrons incident on the neutron detector 11 and emits radiation (hereinafter simply referred to as radiation). Here, in this embodiment, the radiation may be charged particles or gamma rays. When the radiation is charged particles, the dimensions of the micro-region R2 are preferably smaller than the range of the charged particles. Here, the dimensions of the micro-region R2 may mean the dimensions of each micro-region R2, or the average particle size of the micro-region R2. The range of the charged particles may be the range when the charged particles fly through the neutron-capturing material. The charged particles may be charged particles produced when neutrons having a predetermined energy are captured by the neutron-capturing element. The predetermined energy may be the central or lower limit of the energy range of the neutron to be detected. This is a typical energy of the neutron to be detected. If the neutron to be detected is a thermal neutron, the predetermined energy may be, for example, 25 meV, or a lower value than 25 meV (for example, 10 meV).

[0026] The compound semiconductor forming the neutron detector 11 generates electron-hole pairs in response to the radiation. These electron-hole pairs generate an electrical signal (current or voltage) that can be output externally. This electrical signal is output externally via electrodes 12 and 13.

[0027] Compound semiconductors and neutron capture materials will be explained in more detail below.

[0028] <Compound Semiconductor> A neutron capture element of a neutron capture substance mixed in a compound semiconductor generates radiation (charged particles or gamma rays) by capturing an incoming neutron (that is, a nuclear reaction between the nucleus of the neutron capture element and the neutron). Electron-hole pairs are generated in the compound semiconductor by the radiation. That is, in a compound semiconductor, electrons are excited by radiation and move from the valence band to the conduction band across the band gap, thereby generating electron-hole pairs. A compound semiconductor has a band gap that enables generation of such electron-hole pairs. The band gap may be, for example, within a range of 1.0 eV or more and 2.0 eV or less, but is not limited to a value within this range.

[0029] In one embodiment, such a compound semiconductor (base material) is cadmium telluride (CdTe). In this case, more preferably, Cd in CdTe is an isotope that does not absorb neutrons or hardly absorbs neutrons among its isotopes. Cadmium isotopes that do not absorb neutrons or hardly absorb neutrons are, for example, １１４ Cd, but １１４ Other than Cd, １００ Cd, １１１ Cd, １１２ Cd, and １１６ Cd. The Cd element in CdTe constituting a polycrystalline compound semiconductor is mainly (for example, more than half of) a cadmium isotope that does not absorb neutrons or hardly absorbs neutrons ( １１４ Cd, １００ Cd, １１１ Cd, １１２ Cd, and １１６ any one or a combination of Cd) may be used.

[0030] In a polycrystalline compound semiconductor, output of the electrical signal from the electron-hole pairs described above is unlikely to be hindered at grain boundaries (recombination of electron-hole pairs is unlikely to occur at grain boundaries), and it is sufficient as long as the electrical signal can be output from the electrodes 12 and 13 by the electron-hole pairs described above. Therefore, the compound semiconductor is not limited to CdTe, and may be other materials.

[0031] For example, the compound semiconductor (matrix) described above may have a perovskite structure. A compound semiconductor with a perovskite structure generates electron-hole pairs when exposed to radiation (charged particles or gamma rays), and these electron-hole pairs generate the electrical signal described above. Such a compound semiconductor with a perovskite structure may have the same structure as those used in the power generation layer of a perovskite solar cell.

[0032] Compound semiconductors having such a perovskite structure are ABX ３ The compound may be represented by the formula , where A is a monovalent cation. For example, A may be an alkali metal cation or an organic cation. A specific example of A is the methylammonium cation (CH₂). ３ NH ３ ＋ ), formamidinium cation (NH ２ CHNH ２ ＋ ), or cesium cation (Cs ＋ ) may be, but is not limited to, these. B is a divalent cation. For example, B may be a divalent cation of a transition metal element or a group 13 to group 15 element. A specific example of B is Pb ２＋ Sn ２＋ , or Ge ２＋ However, it is not limited to these. X is a monovalent anion such as a halogen anion. A specific example of X is I －１ , Br －１ , or Cl －１ These may be the cases, but are not limited to these.

[0033] In another example, the compound semiconductor (matrix) mentioned above is copper indium gallium selenide (Cu(InGa)Se ２ ) is also acceptable.

[0034] Furthermore, the semiconductor neutron detector 10 (compound semiconductor) has a structure that suppresses the recombination of electrons and holes generated by radiation, as described above. For example, the compound semiconductor may have a structure that generates an internal electric field (an internal electric field generated by the neutron detector 11 itself) that suppresses the recombination of electrons and holes.

[0035] <Neutron Capture Materials> Neutron capture materials have a higher melting point than compound semiconductors. Furthermore, neutron capture materials have a band gap that is larger than that of compound semiconductors (in some cases, about twice as large or more). Neutron capture materials may be insulators.

[0036] The neutron-capturing element may be, but is not limited to, boron (B), lithium (Li), or gadolinium (Gd). Here, boron is, １０ It may be B. Boron captures incoming neutrons (thermal neutrons), resulting in the release of alpha particles and lithium nuclei as charged particles. The boron in question is B １０ It is fine. Lithium captures incoming neutrons (thermal neutrons), and as a result, alpha particles and tritium ( ３ H) is emitted. Gadolinium captures incoming neutrons (thermal neutrons), resulting in the emission of gamma rays as radiation and internally converted electrons as charged particles.

[0037] Neutron-capturing material may be a nitride, fluoride, oxide, or other compound of boron, lithium, or gadolinium as a neutron-capturing element. Specific examples of neutron-capturing material include boron nitride (BN), lithium fluoride (LiF), or gadolinium oxide (Gd ２ O ３ ) may be, but is not limited to, these. Furthermore, the neutron capture material may be a mixture of any of boron, lithium, or gadolinium in elemental form with a lithium compound, a boron compound, or a gadolinium compound. Note that the neutron capture material present in the compound semiconductor may be one type of compound or element, or multiple types of compounds or elements.

[0038] When the neutron-capturing material is boron, the ranges of the alpha particle and lithium nucleus as charged particles are, for example, about 5 to 10 μm and about 1 to 3 μm, respectively. Therefore, the dimensions of each micro-region R2, or the average particle diameter of the micro-region R2, may be, for example, less than 1 μm.

[0039] When the neutron-capturing material is lithium, the range of the alpha particle as the charged particle is, for example, about 5 to 10 μm. Therefore, the dimensions of each micro-region R2, or the average particle diameter of the micro-region R2, may be, for example, less than 5 μm, less than 3 μm, or less than 1 μm.

[0040] The volume concentration of neutron-capturing material relative to the entire compound semiconductor (or neutron detector 11) may be 10% or more. In this case, the volume concentration may be 10% or more, 15% or more, or 20% or more, and may be 30% or less, 40% or less, or 50% or less.

[0041] <Shape and Thickness of Neutron Detector> The neutron detector 11 may be plate-shaped (e.g., flat plate-shaped) or sheet-shaped, as shown in Figures 1A and 1B, but it may also have a block shape (e.g., a rectangular parallelepiped, cylinder, etc.) or other shapes.

[0042] The neutron detector 11 may have a thickness of 1 mm or more. For example, the neutron detector 11 may have a thickness of 1 mm or more, 3 mm or more, 5 mm or more, or 1 cm or more. The thickness of the neutron detector 11 may be, for example, 10 cm or less, 5 cm or less, or 3 cm or less. However, the thickness of the neutron detector 11 is not limited to these ranges and may be less than 1 mm or greater than 10 cm. Note that the thickness of the neutron detector 11 may mean the minimum value of the dimensions of the neutron detector 11 in any direction (in Figure 1A, the vertical direction in this figure).

[0043] The direction perpendicular to the thickness direction of the neutron detector 11 is defined as the first direction, and the direction perpendicular to both the thickness direction and the first direction is defined as the second direction. The dimensions of the neutron detector 11 in the first direction and the dimensions of the neutron detector 11 in the second direction, or each of them, may be 0.5 cm or more and less than 1 cm, or 1 cm or more and 5 cm or less, or may be within other ranges.

[0044] <Electrodes> The semiconductor neutron detector 10 is equipped with electrodes 12 and 13. The electrodes 12 and 13 are electrically connected to the neutron detector 11 (i.e., a compound semiconductor). The electrodes 12 and 13 are provided to output an electrical signal (current or voltage) generated by electron-hole pairs in the compound semiconductor to the outside, as described above.

[0045] As shown in Figure 1A, one electrode 12 of the pair of electrodes 12 and 13 is electrically connected directly or indirectly to one side surface 11a in the thickness direction of the neutron detector 11, and the other electrode 13 is electrically connected directly or indirectly to the other side surface 11b in the thickness direction of the neutron detector 11.

[0046] In this embodiment, each electrode 12, 13 is connected to the neutron detector 11 so that the electrical signal generated by the electron-hole pairs in the neutron detector 11 as described above can be output to the outside (for example, to the processing device 14 described later). For example, each electrode 12, 13 may be ohmic connected to the neutron detector 11. The material (work function) of each electrode 12, 13 may be selected in this manner. In addition, according to the present invention, if the semiconductor neutron detector 10 is configured so that the electrical signal generated by the electron-hole pairs in the neutron detector 11 as described above can be output to the outside through the electrodes 12, 13 (for example, if the bias voltage is applied to the neutron detector 11 through the electrodes 12, 13 in the direction from one side surface 11a to the other side surface 11b), one or both of the electrodes 12, 13 may be Schottky connected to the neutron detector 11 (i.e., a Schottky barrier may exist between the electrodes 12, 13 and the neutron detector 11). The materials for electrodes 12 and 13 should, for example, be permeable to thermal neutrons. That is, electrodes 12 and 13 are formed from materials that are permeable to thermal neutrons. In one embodiment, the conductive material for electrodes 12 and 13 that is permeable to thermal neutrons is carbon. In this case, either electrode 12 or 13 may be the positive electrode. For example, when a bias voltage is applied to the neutron detector 11 through electrodes 12 and 13 in the direction from one surface 11a or 11b of the neutron detector 11 to the other, the direction in which the bias voltage is applied may determine which of electrodes 12 or 13 becomes the positive electrode. The conductive material for electrodes 12 and 13 should be such that it enables electrodes 12 and 13 to output the electricity generated by the electron-hole pairs as an electrical signal. The conductive material forming electrodes 12 and 13 may be a material that does not transmit visible light. The materials for electrodes 12 and 13 other than carbon may be, for example, aluminum, gold, solder, etc., but are not limited to these.

[0047] One electrode 12 is provided on one side of the neutron detector 11 and is the negative electrode to which electrons from electron-hole pairs generated by radiation from the neutron-capturing element in the neutron detector 11 move. The other electrode 13 is provided on the other side of the neutron detector 11 and is the positive electrode to which holes from electron-hole pairs generated by radiation from the neutron-capturing element in the neutron detector 11 move. For example, the pair of electrodes 12 and 13 are provided so as to sandwich the neutron detector 11, as shown in Figure 1A.

[0048] In the example shown in Figure 1A, one electrode 12 is in contact with a portion of the surface 11a on one side in the thickness direction of the neutron detector 11, but it may also be formed to contact the entire surface 11a. In the example shown in Figure 1A, the other electrode 13 is in contact with the entire surface 11b on the other side in the thickness direction of the neutron detector 11, but it may also be formed to contact a portion of the surface 11b.

[0049] <Processing Device> The semiconductor neutron detection device 10 further comprises a processing device 14 and a display unit 15, as shown in Figure 3 or Figure 4. The processing device 14 can be connected to electrodes 12 and 13 via wires 1 and 2. While connected to electrodes 12 and 13, the processing device 14 measures the amount of neutrons incident on the neutron detector 11 based on the electrical signals output from electrodes 12 and 13.

[0050] Figure 3 shows a semiconductor neutron detection device 10 equipped with the processing device 14 of Configuration Example 1. The configuration example in Figure 3 is suitable for measuring the amount of incident neutrons when a large number of neutrons are incident on the neutron detector 11 at once. For example, the configuration example in Figure 3 is suitable for measuring the amount (number) of neutrons incident on the neutron detector 11 instantaneously (for example, within 1 second).

[0051] The processing unit 14 in the configuration example 1 may have, for example, a measurement unit 14a and a processing unit 14b.

[0052] The measuring unit 14a is, for example, an ammeter or a voltmeter, and can be connected to electrodes 12 and 13 via wires 1 and 2. The measuring unit 14a measures the value of the current or voltage as an electrical signal output from electrodes 12 and 13. During this measurement, a bias voltage may be applied to the neutron detector 11 through electrodes 12 and 13 in the direction from one surface 11a or 11b of the neutron detector 11 to the other. The bias application device for applying this bias voltage may be connected in series with the measuring unit 14a, or it may be built into the measuring unit 14a.

[0053] The processing unit 14b determines the amount of neutrons incident on the neutron detector 11 (hereinafter simply referred to as the incident amount) based on the current or voltage value (hereinafter simply referred to as the measured value) measured by the measurement unit 14a. For example, the processing unit 14b determines the incident amount of incident radiation based on the measured value by the measurement unit 14a and the correspondence between the measured value and the incident amount. This correspondence is the relationship between the incident amount and the value of the current or voltage output from the neutron detector 11 via the electrodes 12 and 13, and is determined experimentally in advance, for example. This correspondence may be stored in the storage unit 14b1 of the processing unit 14b, for example.

[0054] The processing unit 14b displays the calculated incident amount on the display unit 15. The processing unit 14b may also output the calculated incident amount to an external terminal device or storage device. The processing unit 14b may be configured as a computer (for example, a personal computer).

[0055] Figure 4 shows a semiconductor neutron detection device 10 equipped with the processing device 14 of Configuration Example 2. The configuration example in Figure 4 is suitable when the number of neutrons incident on the neutron detector 11 is small, for example, when the number of neutrons incident on the neutron detector 11 at one time is about one, and when measuring the incident amount over a predetermined measurement time. For example, the configuration example in Figure 4 is suitable when measuring the amount (number) of neutrons incident on the neutron detector 11 over a measurement time of 30 seconds or more, 1 minute or more, or 1 hour or more.

[0056] The processing unit 14 in Configuration Example 2 includes a counting unit 14c (counter). In Configuration Example 2, each time a neutron is incident on the neutron detector 11, an electrical signal, which is either a current or a voltage, is input from the electrodes 12 and 13 to the counting unit 14c. The counting unit 14c counts the number of times the target electrical signal is input over a predetermined measurement time, and determines this count as the number of neutrons incident on the neutron detector 11 over the measurement time (i.e., the amount of incident). At this time, the target electrical signal that the counting unit 14c counts may be an electrical signal with a pulse height value within a predetermined range. That is, the counting unit 14c does not count electrical signals with pulse height values ​​outside the predetermined range in the number of times the target electrical signal is input.

[0057] The display unit 15 displays the amount of incident light determined by the counting unit 14c. The counting unit 14c may also output the determined amount of incident light to an external terminal device or storage device.

[0058] (Method for manufacturing a semiconductor neutron detection device) Figure 5 is a flowchart showing a method for manufacturing a semiconductor neutron detection device 10 according to an embodiment of the present invention. This manufacturing method is a method for manufacturing the semiconductor neutron detection device 10 described above, and comprises steps S1 to S4.

[0059] In step S1, a powder assembly is prepared by mixing the compound semiconductor material powder described above (hereinafter referred to as the base material powder), the neutron capture material powder described above (hereinafter referred to as the added powder), and a flux powder with a melting point lower than the melting point of the compound semiconductor material (hereinafter referred to as the flux powder). In one embodiment, the compound semiconductor material is CdTe, the neutron capture material is BN, and the flux is CdCl ２ That is the case.

[0060] The flux is CdCl ２ Not limited to zinc chloride (ZnCl ２ ) or other substances.

[0061] Step S1 may include steps S11 and S12.

[0062] In step S11, a mixed powder is prepared by mixing the base material powder, the additive powder, and the flux powder. The base material powder, the additive powder, and the flux powder may be prepared using, for example, a known milling apparatus or an apparatus using a crucible.

[0063] Each particle of the added powder corresponds to the fine region R2 described above. Therefore, the dimensions of each particle of the added powder, or the average particle size of the particles of the added powder, are the same as those of the fine region R2 described above, and may be on the order of micrometers, for example, less than 5 μm, less than 3 μm, or less than 1 μm. The dimensions of the fine region R2 may be the largest dimension among the dimensions of the fine region R2 (particle R2) in any direction.

[0064] When the neutron capture material is boron, the average particle size of each particle in the added powder, or of the fine region R2, may be less than 1 μm, for example, as in the case of the fine region R2 described above. When the neutron capture material is lithium, the average particle size of each particle in the added powder, or of the fine region R2, may be less than 5 μm, less than 3 μm, or less than 1 μm, for example, as in the case of the fine region R2 described above. Note that each particle in the added powder may have the largest dimension among the dimensions of the particle in any direction (the same applies hereinafter).

[0065] The particle size of the base material powder may be on the order of micrometers, similar to the additive powder, and may be, for example, less than 5 μm, less than 3 μm, or less than 1 μm, but is not limited to this range. The particle size of the flux powder may be on the order of micrometers, similar to the additive powder, and may be, for example, less than 5 μm, less than 3 μm, or less than 1 μm, but is not limited to this range as long as the flux powder functions as a flux in step S2 described below.

[0066] The particles of the base material powder prepared in step S11 are, for example, polycrystalline particles. However, the particles of the base material powder may also be amorphous particles.

[0067] In step S12, the mixed powder prepared in step S12 is pressed to form a molded body of a predetermined shape as a powder aggregate. This predetermined shape may be, for example, plate-like (e.g., flat plate-like) or sheet-like, but may also be other shapes. Step S12 may be performed, for example, by a known powder press molding apparatus.

[0068] In step S2, the powder assembly prepared in step S1 (for example, the molded body obtained in step S12) is heated to form a neutron detector 11 containing a polycrystalline compound semiconductor and a neutron-capturing substance mixed within the compound semiconductor from the base powder. That is, a sintered polycrystalline compound semiconductor body containing particles of the neutron-capturing substance-added powder is obtained.

[0069] Step S2 is performed at a heating temperature and heating time such that the following actions E1 and E2 are obtained. The heating temperature may be the surface temperature of the powder aggregate, and the heating time is the time for heating the molded body at the heating temperature. (E1) By heating in step S2, the base material powder forming the powder aggregate becomes a single continuous polycrystalline body as a whole (each particle of the base material powder may bond to each other by melting their surfaces). (E2) In step S2, the flux contained in the powder aggregate melts when heated, promoting the bonding of the particles of the base material powder and promoting the formation of the polycrystalline body.

[0070] Such a heating temperature is above the melting point of the flux described above, but lower than the melting point of the neutron capture material. Such a heating temperature may be lower than the melting point of the compound semiconductor, but is not limited to this, and may be above the melting point of the compound semiconductor. In this case, in step S2, the powder assembly may be held in a mold that prevents flow so that its overall shape is maintained even when it melts.

[0071] The compound semiconductor material is CdTe, the neutron capture material is BN, and the flux is CdCl ２In one embodiment, the heating temperature and heating time can be appropriately set to obtain the effects E1 and E2 described above. In one example, the heating temperature may be about 700°C (for example, 680°C). In this case, the heating time may be about 50 minutes, or other times.

[0072] Since the neutron-capturing material (added powder) has a melting point sufficiently higher than the heating temperature in step S2, it does not melt or diffuse in step S2. In step S2, each particle of the base material powder may melt only on its surface, or both its surface and interior (for example, entirely) may melt.

[0073] In step S3, the neutron detector 11 of the sintered body obtained in step S2 is subjected to alkali metal treatment. This allows the alkali metal to penetrate and act on defects (grain boundaries and surface defects) in the polycrystalline compound semiconductor, making it less likely for the output of the electrical signal by the electron-hole pairs described above to be hindered. The alkali metal treatment can be any known method, for example, immersing the neutron detector 11 in a solution of alkali metal salt dissolved in a solvent. Step S3 may be omitted.

[0074] In step S4, electrodes 12 and 13 are provided to the sintered neutron detector 11. That is, electrodes 12 and 13 are provided so as to be electrically connected to the neutron detector 11.

[0075] In one example, in step S4, the electrode 12 may be formed using carbon paste. That is, a carbon paste containing a large number of conductive carbon particles, a binder, and a solvent is applied to a predetermined area (or the entirety) of one side surface 11a in the thickness direction of the neutron detector 11, and then the carbon paste is heated to form the electrode 12 using the conductive carbon particles, which are the main material of the carbon paste.

[0076] An electrode 13 may be formed on a predetermined area (or the entirety) of the other side surface 11b of the neutron detector 11 in the same manner as the electrode 12 on the other side surface 11a, or it may be formed as follows: When heating the molded body formed in step S12 in step S2, the molded body may be placed on a plate-shaped electrode 13 (for example, an electrode 13 made of conductive carbon) while the heating in step S2 is performed, causing the other side surface 11b (bottom surface) in the thickness direction to melt slightly and bond with the electrode 13.

[0077] The method for providing electrodes 12 and 13 is not limited to the above, and they may be provided by other methods. For example, in step S4, electrodes 12 and 13 may be formed on one side surface 11a and the other side surface 11b of the sintered neutron detector 11 by methods such as metal deposition, screen printing, photolithography, or inkjet printing.

[0078] After completing step S4, the electrodes 12 and 13 coupled to the neutron detector 11 are connected to the processing unit 14 (measurement unit 14a or counting unit 14c) via the electric wires 1 and 2. The neutron detector 11 obtained in this way can be placed at a desired neutron detection location at a BNCT or non-destructive testing site or nuclear facility to measure the amount of neutrons incident on the neutron detector 11, or to check whether or not neutrons are incident.

[0079] (Effects of this embodiment) According to the semiconductor neutron detection device 10 and its manufacturing method of this embodiment described above, the following effects (A) to (L) can be obtained.

[0080] (A) The semiconductor neutron detection device 10 has a neutron detector 11 that includes a polycrystalline compound semiconductor and a neutron-capturing material mixed within the compound semiconductor. The neutron-capturing material includes a neutron-capturing element that captures neutrons incident on the neutron detector 11 and generates radiation (e.g., charged particles or gamma rays). The compound semiconductor generates electron-hole pairs due to the radiation. These electron-hole pairs generate an electrical signal that can be output to the outside. Based on this electrical signal, the incidence of neutrons (e.g., the amount of incident neutrons) can be detected.

[0081] (B) The neutron detector 11 is configured to have a neutron-capturing material mixed within a polycrystalline compound semiconductor. In one embodiment, such a neutron detector 11 can be manufactured by heating a powder assembly containing a base powder of a compound semiconductor material and an added powder of the neutron-capturing material (for example, after press processing). Therefore, unlike single-crystal compound semiconductor epitaxial films such as those in Patent Document 1, the neutron detector 11 can easily contain the neutron-capturing material at a high concentration (for example, a volume concentration of about 10% or more), and thus the concentration of the neutron-capturing element can be easily increased, and the thickness of the neutron detector 11 can be easily increased (for example, the thickness can be 1 mm or more or 1 cm or more).

[0082] (C) The neutron-capturing material exists as numerous micro-regions dispersed within a polycrystalline compound semiconductor. These numerous micro-regions consist of numerous particles of the added powder. This makes it possible to capture the neutron with a uniformly high probability regardless of where the neutron is incident on the compound semiconductor forming the neutron detector 11.

[0083] (D) The dimensions of each micro-region (particle) of the neutron-capturing material are smaller than the range of the charged particles, which are radiation. This allows charged particles generated from the neutron-capturing elements within the neutron-capturing material to be incident from the micro-region into the compound semiconductor region more reliably without being absorbed by the neutron-capturing material (micro-region), and to output an electrical signal more reliably based on the generated charged particles. This makes it possible to increase the neutron detection sensitivity of the semiconductor neutron detection device 10. In contrast, if a conversion film that converts incident neutrons into charged particles is formed on a semiconductor layer that generates an electric current upon the incidence of charged particles, increasing the thickness of this conversion film will cause charged particles generated from the incident neutrons in the conversion film to be absorbed by the conversion film before they can enter the semiconductor layer. This problem is solved by the above-described configuration (the dimensions of the micro-regions described above).

[0084] (E) By simply increasing the thickness of the neutron detector 11, it is possible to increase the neutron detection sensitivity of the semiconductor neutron detector 10. In contrast, if the conversion film that converts incident neutrons into charged particles is formed on a semiconductor layer that generates an electric current upon the incidence of charged particles, increasing the thickness of this conversion film will cause the charged particles generated from the incident neutrons in the conversion film to be absorbed by the conversion film before they enter the semiconductor layer, thus reducing the neutron detection sensitivity. This problem is solved by the above-described configuration (the dimensions of the micro-region described above).

[0085] (F) Neutron-capturing materials have a larger band gap than compound semiconductors (crystalline materials). For example, neutron-capturing materials are insulators. This helps to suppress the adverse effect of neutron-capturing materials on the output performance of electrical signals generated by electron-hole pairs in compound semiconductors.

[0086] (G) The neutron detector 11 has a plate shape or a sheet shape (for example, a flat panel shape). Therefore, the neutron detector 11 can have one side surface 11a in the thickness direction as a wide detection surface.

[0087] (H) The neutron-capturing material has a higher melting point than the compound semiconductor. As a result, in the manufacturing method of the semiconductor neutron detector 10, when the powder assembly containing the base powder of the compound semiconductor material and the added powder of the neutron-capturing material is heated (for example in step S2 above), the neutron-capturing material does not melt and does not diffuse within the polycrystalline compound semiconductor. This makes it possible to suppress the adverse effect of the neutron-capturing material on the output performance of the electrical signal generated by electron-hole pairs in the compound semiconductor.

[0088] (I) The semiconductor neutron detection device 10 is connectable to electrodes 12 and 13 and includes a processing device 14 that measures the amount of neutrons incident on the neutron detector 11 based on electrical signals output from electrodes 12 and 13. In this way, the amount of neutrons incident on the neutron detector 11 can be measured based on electrical signals, for example, based on the intensity of the electrical signals or the number of times the electrical signals are output.

[0089] (J) In the manufacturing method of the semiconductor neutron detector 10, a powder assembly is prepared by mixing a base material powder of a compound semiconductor material with a powder containing a neutron-capturing substance. By heating the powder assembly, a polycrystalline compound semiconductor is formed from the base material powder, and a neutron detector 11, which is a compound semiconductor containing a neutron-capturing substance, is obtained. As a result, by adjusting the amount of powder containing the neutron-capturing substance, the concentration of the neutron-capturing substance in the compound semiconductor can be easily adjusted to a high level (for example, 10% or more). In other words, the concentration of the neutron-capturing element can be easily increased.

[0090] (K) By heating a powder aggregate that is further mixed with a flux powder of a material with a lower melting point than the compound semiconductor material, the flux melts upon heating, promoting the bonding between particles of the base material powder and facilitating the formation of a single continuous polycrystalline body from the base material powder. Furthermore, during the sintering of the base material powder, the molten flux causes crystals to precipitate at the grain boundaries, making each crystal grain larger. As a result, the amount of grain boundaries in the polycrystalline body is reduced, and a polycrystalline compound semiconductor with stable performance can be obtained.

[0091] (L) CdCl as a flux ２ When using CdCl ２ It acts to deactivate the grain boundaries of polycrystalline compound semiconductors. Also, CdCl as a flux ２ It acts to make the compound semiconductor CdTe weakly p-type. Also, CdCl acts as a flux. ２ It acts to increase the resistance of the compound semiconductor CdTe, for example, CdCl ２ This allows you to adjust the resistance of CdTe.

[0092] (Application Examples) Below, application examples of the semiconductor neutron detection device 10 described above will be explained with reference to Figures 6 and 7. Regarding the semiconductor neutron detection device 10 in the application examples, matters not described below may be the same as in the case described above.

[0093] Figures 6 and 7 show examples of the configuration of a semiconductor neutron detection device 10 equipped with multiple (e.g., many) neutron detectors 11 as described above. Figure 6 shows a case where the processing device 14 has a measurement unit 14a and a processing unit 14b, and Figure 7 shows a case where the processing device 14 has a counting unit 14c. Figures 6 and 7 are views of the support substrate 17, which will be described later, from the thickness direction. In the examples of Figures 6 and 7, the number of multiple neutron detectors 11 arranged on each other is 196, but is not limited to this and may be set as appropriate.

[0094] Multiple (e.g., many) neutron detectors 11 are arranged in two dimensions (e.g., along a virtual plane that is a plane or a curved surface). For example, multiple neutron detectors 11 are arranged along the surface 17a of the support substrate 17.

[0095] In the examples shown in Figures 6 and 7, these neutron detectors 11 have the same dimensions and shape as shown in Figures 6 and 7. These neutron detectors 11 may be arranged facing the same direction and may be arranged two-dimensionally along a virtual plane (the surface 17a of the support substrate 17) perpendicular to their thickness direction. In addition, among the multiple (e.g., many) neutron detectors 11 provided by the semiconductor neutron detection device 10, there may be neutron detectors 11 whose dimensions and / or shapes differ from each other. Furthermore, the dimensions and shape of the neutron detectors 11 may be appropriately set according to the application of the semiconductor neutron detection device 10 (e.g., non-destructive testing or neutron detection in BNCT).

[0096] Each neutron detector 11 may be supported by the support substrate 17 by being attached to the surface 17a of the support substrate 17. Electrodes 12 and 13 are electrically connected to one side surface 11a and the other side surface 11b of each neutron detector 11, respectively.

[0097] The processing unit 14 measures the amount of neutrons incident on each neutron detector 11 based on the electrical signal from the neutron detector 11. The electrodes 12 and 13 of each neutron detector 11 are insulated from the electrodes 12 and 13 of other neutron detectors 11 and connected to the processing unit 14 (measurement unit 14a in Figure 6 or counting unit 14c in Figure 7) via wires (similar to the wires 1 and 2 described above). The electrodes 13 (not shown) on the other side surface 11b of each neutron detector 11 may be connected to the wires via conductive parts in through-holes provided in the support substrate 17, for example. Alternatively, as shown in Figures 6 and 7, these wires may be bundled together and insulated from each other to form a single cable 3, which extends from the support substrate 17 and is connected to the measurement unit 14a.

[0098] If the processing unit 14 has a measurement unit 14a and a processing unit 14b as shown in Figure 6, the measurement unit 14a measures the value of the current or voltage as an electrical signal output from the electrodes 12 and 13 of each neutron detector 11. The processing unit 14b determines the amount of neutrons incident on each neutron detector 11 based on the current or voltage value measured by the measurement unit 14a and the above-described correspondence.

[0099] If the processing unit 14 has a counting unit 14c as shown in Figure 7, the counting unit 14c counts the number of times the target electrical signal is input to the electrodes 12 and 13 of each neutron detector 11 over a predetermined measurement time, and determines this number as the amount of incident on the neutron detector 11.

[0100] The image generation unit 16 generates detection image data based on the amount of incident neutrons on each neutron detector 11 determined by the processing unit 14. The detection image data includes a plurality of pixels corresponding to the positions of the plurality of neutron detectors 11, and each such pixel has a pixel value corresponding to the amount of incident neutrons on the corresponding neutron detector 11. Here, the pixel value is, for example, a value indicating the color or intensity of the pixel constituting the detection image data.

[0101] Furthermore, the processing unit 14 displays the detected image data generated by the image generation unit 16 on the display unit 14c. In the detected image data displayed on the display unit 14c, the position of each pixel relative to the entire detected image data may be the same as the position of the neutron detector 11 corresponding to that pixel relative to the entire group of neutron detectors 11. Note that the processing unit 14 (image generation unit 16) may be configured as a computer (for example, a personal computer).

[0102] In such application examples, the two-dimensional distribution of the incident neutrons can be determined from the inspection image data described above. A flat-panel type neutron detector can be constructed using multiple neutron detectors 11 arranged two-dimensionally as described above.

[0103] Furthermore, multiple (for example, many) neutron detectors 11 may be arranged in a one-dimensional manner (for example, along a predetermined straight line or curve). In this case, other matters may be the same as described above. Also, in Figures 6 and 7, the support substrate 17 is rectangular (square) in plan view, but it is not limited to this shape and can be made into various shapes.

[0104] The present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the technical idea of ​​the present invention. For example, the semiconductor neutron detection device 10 and its manufacturing method according to the embodiments of the present invention do not have to have all of the above-described items, and may have only some of the above-described items.

[0105] Furthermore, to the extent that at least some of the above-mentioned problems can be solved, or to the extent that at least some of the effects described herein can be obtained, one or more of the claims and components described herein can be omitted, or any combination of the claims and components described herein is possible.

[0106] Furthermore, any of the following modification examples 1 to 9 may be adopted individually, or two or more of modification examples 1 to 9 may be adopted in any combination as long as no contradictions arise. In this case, the points not mentioned below may be the same as those described above.

[0107] (Example of modification 1) Between the polycrystalline compound semiconductor described above and each or one of the two electrodes 12 and 13, an intermediate layer may be interposed to facilitate the output of electrical signals from the electron-hole pairs generated in the compound semiconductor from the electrodes 12 and 13. That is, the electrodes 12 and 13 may be electrically connected and coupled to the neutron detector 11 via the intermediate layer.

[0108] For example, if the polycrystalline compound semiconductor described above (e.g., the base material powder of step S11) is p-type CdTe, the intermediate layer formed of n-type semiconductor CdS may be provided between the neutron detector 11 made of the compound semiconductor and one of the electrodes 11 or 12.

[0109] If the polycrystalline compound semiconductor described above has a perovskite structure, the intermediate layer as an electron transport layer may be provided between the neutron detector 11 made of the compound semiconductor and one electrode 11 or 12, and the intermediate layer as a hole transport layer may be provided between the neutron detector 11 and the other electrode 12 or 11.

[0110] The polycrystalline compound semiconductor mentioned above is Cu(InGa)Se ２ In this case, the intermediate layer, which serves as a buffer layer of an n-type semiconductor (e.g., CdS), may be provided between the neutron detector 11 made of the compound semiconductor and one of the electrodes 11 or 12.

[0111] (Example of modification 2) It is not necessary to use a flux in step S11 described above.

[0112] (Example of modification 3) Instead of step S12 described above, a binder (e.g., an organic binder) may be mixed with the mixed powder prepared in step S11 to make a paste containing the mixed powder and the binder, and this paste may be applied to the electrode 13 (e.g., a plate-shaped electrode 13). In this case, by performing step S2 described above (for example, after drying the paste), a neutron detector 11 fired from the applied paste (powder aggregate) may be formed on the electrode 13. The compound semiconductor constituting the neutron detector 11 formed in this way may be a single continuous polycrystalline body.

[0113] (Example of modification 4) Step S12 and Step S2 may be performed simultaneously. That is, the sintered molded body may be obtained as the neutron detector 11 by heating the mixed powder while pressing it (for example, by hot pressing).

[0114] (Example of modification 5) In the configuration example of Figure 3 or Figure 6, the processing unit 14b may be omitted. In this case, the display unit 15 receives the measured value of an electrical signal (voltage or current), and the display unit 15 displays the measured value. A person may look at the displayed measured value and determine whether or not neutrons have been detected. Alternatively, a person may look at the displayed measured value and refer to the correspondence relationship described above to determine the amount of incident neutrons. In this case, the correspondence relationship may be displayed on the display unit 15.

[0115] (Modification Example 6) In the configuration example in Figure 3 or Figure 6, the processing unit 14b determines whether the magnitude of the electrical signal (current or voltage) measured by the measurement unit 14a is greater than or equal to a predetermined value. If the result of this determination is positive, the display unit 15 may display a message to that effect, or the speaker may output a sound to that effect. In the latter case, the display unit 15 may be omitted. The semiconductor neutron detection device 10 according to such modification example 6 may be used for purposes (3) or (4) described above, for example, but may also be used for other purposes.

[0116] (Example of modification 7) In the above description, the neutron capturing material captures neutrons incident on the neutron detector 11 and emits radiation (charged particles or gamma rays), but it may also capture neutrons incident on the neutron detector 11 and emit light (photons). In this case, the neutron capturing material may be, for example, GAGG(Gd ３ Al ２ Ga ３ O １２ ), or lithium glass scintillator ( ６ Li ２ O-SiO ２ It may be a neutron capture material doped with Ce, but is not limited to these. For example, in step S11 described above, such a neutron capture material powder is prepared as the added powder.

[0117] In this modification example 7, the compound semiconductor generates electron-hole pairs due to light emitted from the neutron-capturing material, as described above, and these electron-hole pairs generate the electrical signals described above.

[0118] (Modification Example 8) Instead of steps S1 and S2, the following process may be performed: The compound semiconductor is heated and melted (i.e., the compound semiconductor is liquid), and the neutron capture material powder is mixed in (for example, uniformly dispersed). This mixing may be performed in a temperature environment below the melting point of the neutron capture material. Next, the liquid compound semiconductor is cooled to below its melting point to obtain a neutron detector 11 in which the liquid compound semiconductor containing the powder has solidified. Next, steps S3 and S4 described above may be performed on this neutron detector 11. Note that the flux powder described above may be added to the liquid compound semiconductor.

[0119] (Modification Example 9) In the above, the neutron-capturing material was a compound containing a neutron-capturing element or an elemental neutron-capturing element. However, it is acceptable for the neutron-capturing material to exist as a single stable phase (a number of dispersed micro-regions) containing the compound or elemental neutron-capturing material. For example, the neutron-capturing material may be a solid solution of a substance containing the compound or elemental neutron-capturing material with another substance (for example, the lithium glass scintillator in Modification Example 7).

[0120] 1, 2 Electric wire 3 Cable 10 Semiconductor neutron detection device 11 Neutron detector 11a One side 11b The other side 12, 13 Electrodes 14 Processing device 14a Measurement unit 14b Processing unit 14b1 Storage unit 14c Counting unit 15 Display unit 16 Image generation unit 17 Support substrate

Claims

1. A semiconductor neutron detector comprising a neutron detector that generates an electrical signal that can be output externally by incident neutrons, wherein the neutron detector comprises a polycrystalline compound semiconductor and a neutron-capturing material mixed within the compound semiconductor, the neutron-capturing material contains a neutron-capturing element that captures neutrons incident on the neutron detector and generates radiation or light by such capture, the compound semiconductor generates electron-hole pairs by the radiation or light, and the electrical signal is generated by these electron-hole pairs.

2. The semiconductor neutron detection device according to claim 1, wherein the neutron-capturing material exists as a number of fine regions dispersed within the polycrystalline compound semiconductor.

3. The semiconductor neutron detection device according to claim 2, wherein the dimensions of each of the aforementioned fine regions are smaller than the range of the charged particles that constitute radiation.

4. The semiconductor neutron detection device according to any one of claims 1 to 3, wherein the neutron capturing material has a band gap larger than that of the compound semiconductor.

5. The semiconductor neutron detection device according to claim 4, wherein the neutron capturing material is an insulator.

6. The semiconductor neutron detection device according to any one of claims 1 to 5, wherein the neutron capturing material has a higher melting point than the compound semiconductor.

7. The semiconductor neutron detection apparatus according to any one of claims 1 to 6, wherein the neutron detector is a sintered body of the compound semiconductor in which the neutron-capturing material is present.

8. The semiconductor neutron detection device according to any one of claims 1 to 7, wherein the volume concentration of the neutron-capturing material relative to the entire compound semiconductor is 10% or more.

9. The semiconductor neutron detector according to any one of claims 1 to 8, wherein the neutron detector has a thickness of 1 mm or more.

10. The semiconductor neutron detector according to any one of claims 1 to 9, wherein the neutron detector has a plate shape or a sheet shape.

11. The semiconductor neutron detection device according to any one of claims 1 to 10, wherein the neutron-capturing element is boron, lithium, or gadolinium.

12. The compound semiconductor is cadmium tellurium (CdTe), or a semiconductor having a perovskite structure, or copper indium gallium selenide (Cu(InGa)Se) ２ A semiconductor neutron detection device according to any one of claims 1 to 11.

13. A semiconductor neutron detector according to any one of claims 1 to 12, comprising an electrode electrically connected to the neutron detector, wherein the electrode is provided for outputting the electrical signal to the outside.

14. The semiconductor neutron detection apparatus according to claim 13, comprising a processing device that is connectable to the electrode and measures the amount of neutrons incident on the neutron detector based on the electrical signal output from the electrode.

15. A semiconductor neutron detection apparatus according to claim 14, wherein a plurality of neutron detectors are arranged one-dimensionally or two-dimensionally, the processing apparatus includes an image generation unit that measures the amount of neutrons incident on each neutron detector based on the electrical signal from the neutron detector, and generates detection image data based on the amount of neutrons incident on each neutron detector, the detection image data includes a plurality of pixels corresponding to the positions of the plurality of neutron detectors, and each such pixel has a pixel value corresponding to the amount of neutrons incident on the corresponding neutron detector.

16. A method for manufacturing a semiconductor neutron detector equipped with a neutron detector that generates an electrical signal that can be output externally by an incident neutron, comprising: (S1) preparing a powder assembly by mixing a base material powder of a compound semiconductor material and an added powder of a neutron capturing substance; (S2) heating the powder assembly to form the neutron detector from the base material powder, the neutron capturing substance comprising a polycrystalline compound semiconductor and a neutron capturing substance mixed within the compound semiconductor; the neutron capturing substance comprising a neutron capturing element that captures incident neutrons and generates radiation or light by such capture; the compound semiconductor generates electron-hole pairs by the radiation or light, and the electrical signal is generated by these electron-hole pairs.

17. The manufacturing method according to claim 16, wherein in (S1), a powder aggregate is prepared by further mixing a flux powder of a material with a lower melting point than the compound semiconductor material.

18. The manufacturing method according to claim 16 or 17, wherein in (S1), (S11) a mixed powder is prepared by mixing the base material powder and the added powder, and (S12) a molded body of a predetermined shape is formed as the powder aggregate by press processing the mixed powder.

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