WO2022030156A1 - 電離放射線変換デバイス、電離放射線の検出方法、及び電離放射線変換デバイスの製造方法 - Google Patents

電離放射線変換デバイス、電離放射線の検出方法、及び電離放射線変換デバイスの製造方法 Download PDF

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WO2022030156A1
WO2022030156A1 PCT/JP2021/025295 JP2021025295W WO2022030156A1 WO 2022030156 A1 WO2022030156 A1 WO 2022030156A1 JP 2021025295 W JP2021025295 W JP 2021025295W WO 2022030156 A1 WO2022030156 A1 WO 2022030156A1
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Prior art keywords
ionizing radiation
radiation conversion
substrate
conversion layer
conversion device
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English (en)
French (fr)
Japanese (ja)
Inventor
太佑 松井
幸広 金子
卓之 根上
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Panasonic Intellectual Property Management Co Ltd
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Panasonic Intellectual Property Management Co Ltd
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
    • G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
    • G01T1/16—Measuring radiation intensity
    • G01T1/24—Measuring radiation intensity with semiconductor detectors

Definitions

  • the present disclosure relates to an ionizing radiation conversion device, a method for detecting ionizing radiation, and a method for manufacturing an ionizing radiation conversion device.
  • Non-Patent Document 1 methyl ammonium iodide is used as a perovskite compound that converts X-rays into electric charges.
  • An object of the present disclosure is to provide an ionizing radiation conversion device having high sensitivity to ionizing radiation.
  • the ionizing radiation conversion device is A first laminated body including a first substrate and a first ionizing radiation conversion layer arranged on the first substrate, and a second including a second substrate and a second ionizing radiation conversion layer arranged on the second substrate.
  • the first ionizing radiation conversion layer contains a first perovskite compound and contains.
  • the second ionizing radiation conversion layer contains a second perovskite compound and contains.
  • the first ionizing radiation conversion layer is arranged between the first substrate and the second substrate.
  • the present disclosure provides an ionizing radiation conversion device having high sensitivity to ionizing radiation.
  • FIG. 1 shows a cross-sectional view of the ionizing radiation conversion device according to the first embodiment.
  • FIG. 2 shows a cross-sectional view of another ionizing radiation conversion device according to the first embodiment.
  • FIG. 3 shows a cross-sectional view of an ionizing radiation conversion device in which the first laminated body and the second laminated body are connected in parallel with each other.
  • FIG. 4 shows a cross-sectional view of an ionizing radiation conversion device consisting of a single laminate.
  • FIG. 5 shows a cross-sectional view of the ionizing radiation conversion device according to the second embodiment.
  • the absorbed ionizing radiation for example, X-ray
  • the ionizing radiation has a high penetrating ability. Therefore, from the viewpoint of the absorbing ability, it is desirable that the ionizing radiation conversion layer is thick.
  • the film thickness of the ionizing radiation conversion layer be less than or equal to the carrier diffusion length.
  • the carrier diffusion length of the polycrystalline perovskite compound is several hundred nm to several ⁇ m, and the carrier diffusion length of the single crystal perobskite compound is about several ⁇ m. If the film thickness is equal to or less than the carrier diffusion length, there is a problem that the ionizing radiation conversion layer cannot sufficiently absorb the ionizing radiation.
  • the ionizing radiation conversion layer is used as a sensor, it is possible to apply an external voltage to take out the carrier, but if the film thickness of the ionizing radiation conversion layer is large, the external voltage required for taking out the carrier becomes large. .. As a result, there arises a problem that the S / N ratio decreases due to the increase in dark current.
  • the ionizing radiation conversion device of the present disclosure by stacking a plurality of laminated devices having a thin film ionizing radiation conversion layer that facilitates carrier extraction, the ionizing radiation is sufficiently absorbed and the generated carriers are efficiently extracted. Is possible.
  • ionizing radiation means ⁇ ray, ⁇ ray, neutron beam, proton beam, X-ray, or ⁇ ray.
  • FIG. 1 shows a cross-sectional view of the ionizing radiation conversion device 100 according to the first embodiment.
  • the ionizing radiation conversion device 100 includes a first laminated body 10 and a second laminated body 20.
  • the second laminated body 20 is arranged on the first laminated body 10.
  • the first laminated body 10 has a first substrate 11 and a first ionizing radiation conversion layer 12 arranged on the first substrate 11.
  • the second laminated body 20 has a second substrate 21 and a second ionizing radiation conversion layer 22 arranged on the second substrate 21.
  • the first ionizing radiation conversion layer 12 is arranged between the first substrate 11 and the second substrate 21.
  • the ionizing radiation conversion device 100 has high sensitivity to ionizing radiation. That is, the ionizing radiation conversion device 100 can efficiently convert ionizing radiation into electric charges.
  • the ionizing radiation conversion device 100 can be used, for example, as an ionizing radiation detector, an image pickup device, a dosimeter, or a beta volta battery.
  • the ionizing radiation conversion device 100 may further include a read-out circuit that reads out the electric charge.
  • the readout circuit is electrically connected to the ionizing radiation conversion device 100.
  • the readout circuit may be located inside the first board 11 or may be located outside the first board 11, for example.
  • FIG. 2 shows a cross-sectional view of the ionizing radiation conversion device 200 according to the first embodiment.
  • the first laminated body 10 may further include a first electrode 13.
  • the first ionizing radiation conversion layer 12 is arranged between the first substrate 11 and the first electrode 13.
  • the second laminated body 20 may further include a second electrode 23.
  • the second ionizing radiation conversion layer 22 is arranged between the second substrate 21 and the second electrode 23.
  • the ionizing radiation incident on the ionizing radiation conversion device 200 loses a part of the energy in the first ionizing radiation conversion layer 12 and the second ionizing radiation conversion layer 22 to form electron hole pairs.
  • the holes and electrons generated in the first ionizing radiation conversion layer 12 reach the first substrate 11 and the first electrode 13, respectively, and are taken out to an external circuit.
  • the holes and electrons generated in the second ionizing radiation conversion layer 22 reach the second substrate 21 and the second electrode 23, respectively, and are taken out to an external circuit.
  • the first substrate 11 and the second substrate 21 may be made of glass or plastic. Alternatively, the first substrate 11 and the second substrate 21 may be made of a conductive material.
  • the conductive material may or may not have translucency.
  • An example of a conductive material having translucency is a metal oxide.
  • An example of the metal oxide is (I) Indium-tin composite oxide, (Ii) Antimony-doped tin oxide, (Iii) Fluorine-doped tin oxide, (Iv) zinc oxide doped with at least one element selected from the group consisting of boron, aluminum, gallium, and indium, or (v) a complex thereof.
  • non-transmissive conductive materials include platinum, gold, silver, copper, aluminum, rhodium, indium, titanium, iron, nickel, tin, zinc, or alloys containing any of these, or conductivity. It is a carbon material of.
  • Both the first electrode 13 and the second electrode 23 are made of a conductive material. Examples of conductive materials are as described above.
  • At least one selected from the group consisting of the first substrate 11, the first electrode 13, the second substrate 21, and the second electrode 23 may be made of a material having no translucency. As a result, the resistance value of the electrode can be suppressed to a low level, and the performance of the ionizing radiation conversion device is improved.
  • an electrode may be further provided between the first substrate 11 and the first ionizing radiation conversion layer 12.
  • the electrode is made of a conductive material.
  • an electrode may be further provided between the second substrate 21 and the second ionizing radiation conversion layer 22.
  • the electrode is made of a conductive material.
  • the first laminated body 10 When the ionizing radiation conversion device 200 is connected to an external circuit, the first laminated body 10 may be connected in series with the second laminated body 20 or may be connected in parallel.
  • the first laminated body 10 does not have to be in contact with the second laminated body 20.
  • Another layer may be arranged between the first laminated body 10 and the second laminated body 20.
  • An example of another layer may be an insulating layer.
  • the insulating layer is composed of an insulating material.
  • the insulating material may be an organic insulating material or an inorganic insulating material. Examples of organic insulating materials are epoxy resins, silicone resins, or polyimides. Examples of inorganic insulating materials are silicon oxide, silicon nitride, silicon nitride, hafnium oxide, aluminum oxide, and tantalum oxide.
  • the insulating layer may be made of glass or plastic.
  • FIG. 3 shows a cross-sectional view of an ionizing radiation conversion device 200 in which the first laminated body 10 and the second laminated body 20 are electrically connected in parallel with each other.
  • the first laminated body 10 is electrically connected in parallel with the second laminated body 20 by the lead wire 14.
  • the parallel connection increases the current value taken out to the external circuit, so that the performance of the ionizing radiation conversion device 200 is improved.
  • FIG. 4 shows a cross-sectional view of an ionizing radiation conversion device 300 made of a single laminated body. As an example of a single laminated body, the first laminated body 10 is shown.
  • the ionizing radiation conversion layer can be made thinner as compared with the ionizing radiation conversion device 300. As a result, the distance that the generated carriers move to the electrodes is shortened, so that the carrier loss is small and the carriers can be efficiently taken out to the external circuit.
  • Ionizing radiation may be detected by detecting the electric charge generated by irradiating the first perovskite compound and the second perovskite compound with ionizing radiation. According to the above detection method, ionizing radiation can be detected with high sensitivity.
  • the "perovskite compound” is a compound represented by ABX 3 or an analog thereof.
  • the compound represented by ABX 3 is, for example, BaTiO 3 , MgSiO 3 , CsPbI 3 , CsPbBr 3 or (CH 3 NH 3 ) PbI 3 .
  • the methylammonium cation that is, CH 3 NH 3+
  • MA the methylammonium cation
  • the analog of the compound represented by ABX 3 has the following structure (i) or (ii).
  • the first perovskite compound and the second perovskite compound may independently contain two or more kinds of cations and one or more kinds of monovalent anions.
  • the perovskite compound may substantially consist of two or more cations and one or more monovalent anions.
  • a perovskite compound is substantially composed of two or more cations and one or more monovalent anions" means that two or more cations are used with respect to the total amount of substance of all the elements constituting the perovskite compound. And it means that the total amount of substance of one or more monovalent anions is 90 mol% or more.
  • the perovskite compound may consist of two or more cations and one or more monovalent anions.
  • the two or more cations may contain at least one selected from the group consisting of Pb 2+ , Sn 2+ , Ge 2+ , and Bi 3+ .
  • the monovalent anion is, for example, a halogen anion or a composite anion.
  • halogen anions are fluorine anions, chlorine anions, bromine anions, or iodine anions.
  • composite anions are SCN-, NO 3- , or HCOO- .
  • the perovskite compound may be, for example, a compound represented by ABX 3 (A is a monovalent cation, B is a divalent cation, and X is a halogen anion). Since such a perovskite compound has a high ability to absorb ionizing radiation and a long carrier diffusion length, the ionizing radiation can be efficiently converted into an electric signal.
  • Examples of monovalent cations are organic cations or alkali metal cations.
  • organic cations are MA, formamidinium cations (ie NH 2 CHNH 2+ ), phenylethylammonium cations (ie C 6 H 5 C 2 H 4 NH 3 + ), or guanidinium cations (ie NH 2 CHNH 2 +). CH 6 N 3 + ).
  • alkali metal cations examples include cesium cations (ie, Cs + ) or rubidium cations (ie, Rb + ).
  • divalent metal cations examples include lead cations (ie, Pb 2+ ), tin cations (ie, Sn 2+ ), or germanium cations (ie, Ge 2+ ).
  • the divalent metal cation may be Pb 2+ .
  • Perovskite compounds include, for example, CH 3 NH 3 PbI 3 , CH 3 CH 2 NH 3 PbI 3 , HC (NH 2 ) 2 PbI 3 , CH 3 NH 3 PbBr 3 , CH 3 NH 3 PbCl 3 , CsPbI 3 , or CsPbBr. It is 3 .
  • the difference between the band gap of the first perovskite compound and the band gap of the second perovskite compound may be 0.1 eV or less.
  • the first perovskite compound may be the same as the second perovskite compound.
  • Each of the first ionizing radiation conversion layer 12 and the second ionizing radiation conversion layer 22 may have a thickness of 0.1 ⁇ m or more. Each of the first ionizing radiation conversion layer 12 and the second ionizing radiation conversion layer 22 may have a thickness of 0.1 ⁇ m or more and 1 cm or less. Each of the first ionizing radiation conversion layer 12 and the second ionizing radiation conversion layer 22 may have a thickness of 100 ⁇ m or more and 1 mm or less.
  • the first ionizing radiation conversion layer 12 may have a thickness different from that of the second ionizing radiation conversion layer 22.
  • the first ionizing radiation conversion layer 12 may contain 30 mol% or more of the first perovskite compound.
  • the first ionizing radiation conversion layer 12 may contain 80 mol% or more of the first perovskite compound.
  • the first ionizing radiation conversion layer 12 may be composed of only the first perovskite compound.
  • the second ionizing radiation conversion layer 22 may contain 30 mol% or more of the second perovskite compound.
  • the second ionizing radiation conversion layer 22 may contain 80 mol% or more of the second perovskite compound.
  • the second ionizing radiation conversion layer 22 may be composed of only the second perovskite compound.
  • the perovskite compound may be used as a scintillator.
  • the same can be achieved by arranging an element such as a photodiode that converts light into an electric signal between the first ionizing radiation conversion layer 12 containing the perovskite compound and the first substrate 11. The effect of is obtained.
  • the first electrode 11 is not provided, and the first substrate 11 may be a glass substrate or a plastic substrate.
  • FIG. 5 shows a cross-sectional view of the ionizing radiation conversion device 400 according to the second embodiment.
  • the ionizing radiation conversion device 400 includes a third laminated body 30 in addition to the first laminated body 10 and the second laminated body 20.
  • the second laminated body 20 is arranged between the first laminated body 10 and the third laminated body 30.
  • the third laminated body 30 has a third substrate 31, a third ionizing radiation conversion layer 32, and a third electrode 33.
  • the third ionizing radiation conversion layer 32 is arranged between the third substrate 31 and the third electrode 33.
  • the ionizing radiation conversion device 400 has higher sensitivity to ionizing radiation. That is, the ionizing radiation conversion device 400 can more efficiently convert the ionizing radiation into electric charges.
  • the material constituting the third substrate 31 and the third electrode 33 may be the conductive material described in the first embodiment.
  • At least two laminates selected from the group consisting of the first laminate 10, the second laminate 20, and the third laminate 30 may be electrically connected in parallel with each other.
  • the parallel connection increases the current value taken out to the external circuit, so that the performance of the ionizing radiation conversion device 400 is improved.
  • the ionizing radiation conversion device of the present disclosure for example, four or more laminated bodies may be laminated in order to convert ionizing radiation more efficiently. That is, the ionizing radiation conversion device of the present disclosure may include four or more ionizing radiation conversion layers. In the ionizing radiation conversion device of the present disclosure, for example, 10 or more laminated bodies may be laminated. That is, the ionizing radiation conversion device of the present disclosure may include 10 or more ionizing radiation conversion layers.
  • the method for manufacturing an ionizing radiation conversion device includes a first step of preparing a first substrate 11 and a second step of forming a first ionizing radiation conversion layer 12 containing a perovskite compound on the first substrate 11.
  • the first substrate 11 is prepared.
  • the first substrate 11 may have a read-out circuit.
  • the pixel pitch is, for example, 125 micrometers.
  • the first ionizing radiation conversion layer 12 containing the first perovskite compound is formed on the first substrate 11.
  • a raw material is prepared so that the first perovskite compound has a desired composition.
  • the raw material of the first perovskite compound is dissolved in a solvent to obtain a precursor solution of the first ionizing radiation conversion layer 12.
  • the first ionizing radiation conversion layer 12 is formed.
  • the second step will be described.
  • raw materials for the first perovskite compound for example, 0.92 mol / L PbI 2 , 0.17 mol / L PbBr 2 , 0.83 mol / L formamidinium iodide, 0.17 mol / L methylammonium bromide. , And 0.05 mol / L CsI are prepared. These materials are dissolved in a mixed solvent of dimethyl sulfoxide and N, N-dimethylformamide. As a result, a precursor solution of the first ionizing radiation conversion layer 12 containing the perovskite compound is obtained.
  • the mixing ratio of dimethyl sulfoxide and N, N-dimethylformamide is, for example, 1: 4 (volume ratio).
  • the first ionizing radiation conversion layer 12 is formed by applying the precursor solution, for example, by an inkjet method.
  • the first electrode 13 is formed on the first ionizing radiation conversion layer 12.
  • a first electrode 13 made of gold is formed by a thin-film deposition method.
  • the first electrode 13 has a thickness of, for example, 100 nanometers. In this way, the first laminated body 10 is obtained.
  • the second laminated body 20 is obtained in the same manner as the first laminated body 10.
  • the second laminated body 20 By arranging the second laminated body 20 on the first laminated body 10, an ionizing radiation conversion device can be obtained. As described above, the second ionizing radiation conversion layer 22 having the second ionizing radiation conversion layer 22 arranged on the second substrate 21 is placed on the first laminated body 10 having the first ionizing radiation conversion layer 12 arranged on the first substrate 11. 2 The laminated body 20 may be formed.
  • the method for detecting ionizing radiation of the present disclosure is a method of detecting ionizing radiation using the above-mentioned ionizing radiation conversion device of the present disclosure.
  • the method for detecting ionizing radiation of the present disclosure is, for example, the first laminated body 10 including the first ionizing radiation conversion layer 12 arranged on the first substrate 11 and the first substrate 11, and the second substrate 21 and the first.
  • An ionizing radiation conversion device containing 2 perovskite compounds and the second laminated body 20 being laminated on the first laminated body 10 is used.
  • the charge or light generated by irradiating the first perovskite compound and the second perovskite compound with ionizing radiation by the ionizing radiation conversion device is detected.
  • the ionizing radiation conversion device of the present disclosure is used, for example, in an ionizing radiation detector.

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PCT/JP2021/025295 2020-08-06 2021-07-05 電離放射線変換デバイス、電離放射線の検出方法、及び電離放射線変換デバイスの製造方法 Ceased WO2022030156A1 (ja)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2019520565A (ja) * 2016-06-08 2019-07-18 コーニンクレッカ フィリップス エヌ ヴェＫｏｎｉｎｋｌｉｊｋｅ Ｐｈｉｌｉｐｓ Ｎ．Ｖ． 位相コントラスト撮像及び／又は暗視野撮像のための分析格子
JP2019526782A (ja) * 2016-06-07 2019-09-19 コーニンクレッカ フィリップス エヌ ヴェＫｏｎｉｎｋｌｉｊｋｅ Ｐｈｉｌｉｐｓ Ｎ．Ｖ． 直接光子変換検出器
WO2020003603A1 (ja) * 2018-06-26 2020-01-02 国立大学法人京都大学 放射線検出器、及び放射線検出器の製造方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2019526782A (ja) * 2016-06-07 2019-09-19 コーニンクレッカ フィリップス エヌ ヴェＫｏｎｉｎｋｌｉｊｋｅ Ｐｈｉｌｉｐｓ Ｎ．Ｖ． 直接光子変換検出器
JP2019520565A (ja) * 2016-06-08 2019-07-18 コーニンクレッカ フィリップス エヌ ヴェＫｏｎｉｎｋｌｉｊｋｅ Ｐｈｉｌｉｐｓ Ｎ．Ｖ． 位相コントラスト撮像及び／又は暗視野撮像のための分析格子
WO2020003603A1 (ja) * 2018-06-26 2020-01-02 国立大学法人京都大学 放射線検出器、及び放射線検出器の製造方法

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