Bipolar charge transfer halide semiconductor single crystal for high-energy radiation detection and preparation method and application thereof

Abstract

The invention belongs to the technical field of halide semiconductor nuclear detection, and particularly relates to a bipolar charge transfer halide semiconductor single crystal for high-energy radiation detection and a preparation method and application thereof. The general formula of the crystal is Cs1-xAxPb1-yByBr3-zXz, A is one or more of Na, K, Rb, Cu, Tl and H3O, B is one or more of Si, Ge, Sn, Mg, Ca, Sr, Ba, Zn, Cd and Hg, X is one or more of F, Cl, I, BF4, HCOO, OH, CN, SCN, NCS, SH, NO3 and H2POO, 0 < = x < = 1, 0 < = y < = 1, and 0 < = z < = 3. Zone-melting purification is combined with the vertical Bridgman method, the crack-free large-size high-quality single crystal is prepared, the crystal yield and the device uniformity are improved, bipolar charge transfer is achieved, the device structure is simplified, and the method can be widely applied to the field of nuclear detection.

Description

Technical Field

[0001] The present invention belongs to the technical field of halide semiconductor nuclear detection, and particularly relates to a halide semiconductor single crystal with bipolar charge transport for high-energy radiation detection, a preparation method thereof, and an application thereof. Background Art

[0002] Metal halide perovskites have excellent chemical stability, an ideal band gap, a large average atomic number, a high density, and excellent carrier transport properties, etc., making them promising to become a new generation of room-temperature nuclear radiation detection materials. In order to ensure that the detector has a high absorption efficiency for high-energy rays, single crystals with a certain size and thickness are generally required. For example, a 24-mm-thick cesium lead bromide (CsPbBr3) has an absorption efficiency of only 63% for 662-keV 137 Csγ photons. Currently, the methods commonly used for growing halide perovskite crystals mainly include the low-temperature solution method and the melt method. However, in the solution method, due to the limited solubility of the solute and the easy formation of complexes with the solvent, the crystal growth rate and yield are low. In addition, limited by the purity of the raw materials and the solvent, the grown crystals have more impurities and defects, so it is difficult to batch-produce large-size and uniform-performance crystals by the solution method. The melt method is a commonly used method for preparing large-size single crystals, which mainly involves heating and melting polycrystalline materials in a crucible with a certain shape and size and then performing directional solidification for crystal growth. However, the low thermal conductivity of all-inorganic perovskites and low-temperature structural phase transitions, such as the cesium lead bromide having structural phase transitions from cubic to tetragonal and then to orthorhombic at 130 °C and 88 °C, result in the easy generation of defects such as cracks and twins in the crystal, affecting the crystal quality and single crystal ratio. In addition, halide perovskites are ionic crystals, and a large number of intrinsic point defects, secondary phases, etc. are easily generated during the preparation process, as well as impurity atoms in the raw materials, all of which will affect the carrier transport performance in the crystal, thereby deteriorating the performance and uniformity of the detector. Therefore, as a potential high-energy radiation detection material, halide perovskite semiconductors urgently need process optimization to improve the detector performance and uniformity and achieve the stable and controllable preparation of large-volume single crystals with bipolar charge transport.

[0003] So far, many domestic and foreign institutions have carried out research on the growth and properties of perovskite crystals using the Bridgman method. In 2013, Stoumpos et al. first grew CsPbBr3 single crystals with a size of Φ7mm×12mm using the Bridgman method and characterized their structure and optoelectronic properties (C.C. Stoumpos, et al. Crystal Growth & Design, 2013, 13(7): 2722-2727.). Subsequently, Song et al. and Zhang et al. grew CsPbBr3 crystals with sizes of Φ25mm×70mm and Φ24mm×90mm respectively using the Bridgman method by optimizing the overheating temperature of CsPbBr3 polycrystalline materials and the pretreatment of raw materials. In the same year, He et al. grew high-purity CsPbBr3 single crystals with a size of Φ11mm×60mm and achieved an energy resolution of 3.8% for 662keV 137 Csγ rays at room temperature using an asymmetric electrode (Y. He, et al. Nature Communications, 2018, 9(1): 1609.). In addition, He et al. designed quasi-hemispherical and pixel-type device structures based on single-carrier CsPbBr3 crystals to improve the charge collection efficiency and achieved an energy resolution of 1.4% for 662keV 137 Csγ rays (Y. He, et al. Nature Photonics, 2021, 15(1): 36-42.).

[0004] Although significant progress has been made in the crystal growth and detector performance of halide perovskites, there are still many problems. For example, the intrinsic point defects and secondary phases caused by raw material impurities and process instability significantly affect the carrier transport performance, thus limiting the performance and uniformity of the devices. In addition, there is a structural phase transition of perovskite materials from cubic to tetragonal and then to orthorhombic phases, which makes the crystals prone to cracking and increases the difficulty of preparing large-size crystals; moreover, most current halide perovskite crystals are still based on single-carrier collection modes, so special device designs (quasi-hemispherical, pixel-type, etc.) are needed to improve the charge collection efficiency to achieve high-energy resolution detection. Summary of the Invention

[0005] The disadvantages of the prior art are as follows:

[0006] (1) To ensure the absorption efficiency of the detector for high-energy rays, a single crystal with a certain size and thickness is generally required. However, halide perovskite crystals have a low thermal conductivity, and there is a structural phase transition at low temperatures, which inevitably generates stress during the crystal growth process, thereby inducing the formation of cracks, seriously affecting the crystal quality and single crystal rate. Currently, the size of single crystals of halide semiconductors available for radiation detection is still limited, usually not exceeding 1 inch, and the crystal quality is unstable, which to a certain extent limits the large-scale application of devices.

[0007] (2) The high detection efficiency of halide semiconductor detectors depends on the excellent carrier transport properties of the crystals. However, currently reported perovskite crystals have a large number of impurity atoms, and intrinsic defects (point defects, secondary phases, etc.) are easily formed during the preparation process, and high hole carrier transport performance (~10 -3 cm 2 V -1 ) cannot be obtained, which limits the detector performance and reduces its uniformity, and the yield is relatively low.

[0008] (3) Currently, most perovskite crystals are still based on the single-carrier collection mode of hole transport, and complex device designs (quasi-hemispherical, pixel type, etc.) are required to improve the charge collection efficiency to achieve high-energy resolution detection.

[0009] To solve the above existing technical problems, the present application provides the following technical solutions:

[0010] The present invention provides a method for preparing a halide semiconductor single crystal with bipolar charge transport for high-energy radiation detection, including the following steps:

[0011] S11: Load CsBr and PbBr2 into a crucible and seal it;

[0012] S12: In a tube furnace, keep the crucible at 570 - 650 °C for 24 - 36 h, and after cooling to room temperature (25 ± 5 °C), perform 1 - 20 zone melting cycles at 570 - 620 °C to obtain a CsPbBr3 polycrystalline ingot;

[0013] S13: Overheat the crucible containing the CsPbBr3 polycrystalline ingot in a crystal growth furnace and then perform downward heat preservation; the crucible may or may not contain an ABX3 polycrystalline ingot, and the ABX3 polycrystalline ingot is obtained from AX and BX2 according to the methods of steps S11 and S12;

[0014] S14: Use the vertical Bridgman method to grow perovskite crystals in the crucible for 100 - 600 h;

[0015] S15: Cool the crucible to 300 - 400 °C in 48 - 72 h and perform heat preservation annealing for 12 - 24 h;

[0016] S16: After cooling the crucible, take out the product to obtain the halide semiconductor single crystal;

[0017] The chemical formula of the halide semiconductor single crystal is Cs 1-x A x Pb 1-y B y Br 3-z X z , where A is selected from one or more of Na, K, Rb, Cu, Tl, and H3O, B is selected from one or more of Si, Ge, Sn, Mg, Ca, Sr, Ba, Zn, Cd, and Hg, X is selected from one or more of F, Cl, I, BF4, HCOO, OH, CN, SCN, NCS, SH, NO3, and H2POO, and 0 ≤ x ≤ 1, 0 ≤ y ≤ 1, 0 ≤ z ≤ 3.

[0018] Preferably, the crucible is a quartz crucible.

[0019] Preferably, in step S11, the crucible is pretreated. The pretreatment method is to wash it with deionized water for 5 - 10 min, then soak it in acetone for 12 - 24 h, then wash it with deionized water for 5 - 10 min, then soak it in aqua regia for 24 - 36 h, then wash it with deionized water for 5 - 10 min, and dry it at 120 - 150 °C for 12 - 24 h.

[0020] Preferably, in step S12, the method for preparing the CsPbBr3 polycrystalline ingot includes the following steps:

[0021] S21: In a tube furnace, heat the crucible to 250 - 400 °C within 6 - 12 h and keep it warm for 2 - 4 h;

[0022] S22: Heat the crucible at a rate of 10 - 20 °C / h to 570 - 650 °C and keep it warm for 24 - 36 h for polycrystalline material synthesis;

[0023] S23: Cool the crucible to room temperature within 10 - 12 h and then perform 1 - 20 zone melting cycles in a furnace at 570 - 620 °C to obtain the CsPbBr3 polycrystalline ingot.

[0024] Preferably, in step S12, the zone melting cycle uses a three - temperature - zone furnace. The method is to move the heater from one end of the crucible to the other end at a rate of 5 - 100 mm / h until it passes through the entire crucible, and then move the heater back to the initial position for the next zone melting process.

[0025] Preferably, in step S13, the crucible containing the CsPbBr3 polycrystalline ingot is obtained by breaking the CsPbBr3 polycrystalline ingot after removing the front end and the tail end, re - adding it to the crucible, and then vacuum - sealing it.

[0026] Preferably, in step S13, the crystal growth furnace is selected from a four-zone Bridgman crystal growth furnace.

[0027] Preferably, in step S13, during overheating, the bottom of the crucible is at 550-650 °C for 24-36 h; during heat preservation, the bottom of the crucible is at 500-600 °C and heat preservation is carried out for 4-6 h.

[0028] Preferably, in step S14, during the growth of the perovskite crystal, the ACRT rotation control system is used to alternately perform forward rotation and reverse rotation, and at the same time, it descends at a rate of 0.1-10 mm / h.

[0029] Further, the method of alternately performing forward rotation and reverse rotation is to accelerate from 0 r / min to 1-50 r / min in the positive direction in 1-30 s, rotate at a constant speed for 0-50 s, then decelerate to 0 r / min in 1-30 s, and maintain for 0-50 s; then accelerate from 0 r / min to 1-50 r / min in the reverse direction in 1-30 s, rotate at a constant speed for 0-50 s, and then decelerate to 0 r / min in 1-30 s, and maintain for 0-50 s.

[0030] Preferably, in step S16, the cooling method is: cooling at a rate of 15-30 °C / h to 150-200 °C, and heat preservation is carried out for 4-8 h; then slowly cooling to room temperature at a rate of 3-5 °C / h.

[0031] Specifically, the preparation method of the halide semiconductor single crystal for high-energy radiation detection with bipolar charge transport includes the following steps:

[0032] 1. Rinse the quartz crucible with deionized water for 5-10 min, then soak it in an acetone solution for 12-24 h to remove residual organic substances on the crucible wall, etc.; then rinse it with deionized water for 5-10 min, and soak it in aqua regia (concentrated hydrochloric acid: concentrated nitric acid = 3:1) for 24-36 h to remove other impurities on the crucible wall; finally, rinse it with deionized water for 5-10 min and place it in an oven to dry at 120-150 °C for 12-24 h to remove residual moisture on the crucible wall;

[0033] 2. In order to reduce the influence of impurity elements, CsBr and PbBr2 with a purity ≥ 4N (99.99%) are selected as the initial raw materials; when weighing the raw materials, in order to avoid the influence of water and oxygen in the air, the weighing is carried out in a dry glove box, and the raw materials are weighed strictly according to the stoichiometric ratio; load them into the quartz crucible treated in step 1, and then evacuate the quartz crucible to below 5×10 -4 Pa, and use a hydrogen-oxygen flame for welding and sealing;

[0034] 3. Place the quartz crucible sealed in Step 2 into a two-temperature-zone tube furnace, and heat it to 250 - 400 °C within 6 - 12 h. After holding for 2 - 4 h, slowly heat it to 570 - 650 °C at a rate of 10 - 20 °C / h, and hold for 24 - 36 h for perovskite polycrystalline material synthesis; finally, cool it to room temperature within 10 - 12 h to obtain a quartz crucible filled with CsPbBr3 polycrystalline material;

[0035] 4. Place the quartz crucible obtained in Step 3 above into a three-temperature-zone zone melting furnace, heat the three heaters to the program-set temperature within 6 - 12 h for holding, move the heater so that it gradually moves from one end of the quartz crucible to the other end at a rate of 5 - 100 mm / h until it passes through the entire quartz crucible; then quickly move the heater back to the initial position for the next zone melting process. After 1 - 20 zone melting cycles, obtain a zone-melted CsPbBr3 polycrystalline ingot;

[0036] 5. Select AX and BX2 with a purity ≥ 4N (99.99%) as the initial raw materials, and repeat the operations in Step 2, Step 3, and Step 4 to obtain zone-melted ABX3 polycrystalline ingots of other components;

[0037] 6. Remove the front one-third and the tail one-third of the zone-melted CsPbBr3 and ABX3 polycrystalline ingots obtained in Step 4 and Step 5 above, and only retain the middle one-third area of the polycrystalline ingot; and weigh, mix, and crush the middle areas of the zone-melted polycrystalline ingots of different components according to a certain stoichiometric ratio, and then reload them into the quartz crucible treated in Step 1, evacuate to below 5×10 -4 Pa, and seal it with a hydrogen-oxygen flame;

[0038] 7. Repeat Step 3 for the quartz crucible sealed in Step 6 above to obtain zone-melted perovskite polycrystalline material with the composition of Cs 1-x A x Pb 1-y B y Br 3-z X z ;

[0039] 8. Place the quartz crucible obtained in Step 7 above into a four-temperature-zone Bridgman crystal growth furnace, heat it to the program-set temperature within 10 - 15 h, and then move the crucible so that its lowest end is superheated at 550 - 650 °C for 24 - 36 h to ensure that the polycrystalline material in the crucible is completely melted and homogenized;

[0040] 9. Slowly lower the quartz crucible after overheating in the above step 8 so that the temperature at its lowest end is between 500 and 600 °C and keep it warm for 4 to 6 h. Turn on the ACRT rotation control system, which can rotate forward, reverse, and alternately forward and reverse. The rotation speed is adjustable from 0 to 50 r / min, the rotation time is adjustable from 0 to 50 s, the stop time is adjustable from 0 to 50 s, and the time for the rotation speed to accelerate (decelerate) from 0 (or maximum) to maximum (0) is adjustable from 1 to 30 s. At the same time, control the quartz crucible to descend at a rate of 0.1 to 10 mm / h to grow perovskite crystals. After growing for 100 to 600 h, stop the descent of the crucible and turn off the ACRT control system;

[0041] 10. Cool down the four-zone Bridgman furnace after growth in the above step 9. Slowly cool the four zones simultaneously to 300 to 400 °C within 48 to 72 h, keep it warm for 12 to 24 h for in-situ annealing to eliminate stress; then cool it down to 150 to 200 °C at a rate of 15 to 30 °C / h and keep it warm for 4 to 8 h; then slowly cool it to room temperature at a rate of 3 to 5 °C / h, turn off the power supply, take out the quartz crucible, and the crystal growth is completed.

[0042] The present invention also provides a halide semiconductor single crystal for high-energy radiation detection with bipolar charge transport prepared by the above preparation method. The chemical formula of the halide semiconductor single crystal is Cs 1-x A x Pb 1-y B y Br 3-z X z , where A is selected from one or more of Na, K, Rb, Cu, Tl, and H3O, B is selected from one or more of Si, Ge, Sn, Mg, Ca, Sr, Ba, Zn, Cd, and Hg, X is selected from one or more of F, Cl, I, BF4, HCOO, OH, CN, SCN, NCS, SH, NO3, and H2POO, and 0 ≤ x ≤ 1, 0 ≤ y ≤ 1, 0 ≤ z ≤ 3.

[0043] The present invention also provides a nuclear radiation detector using the above halide semiconductor single crystal for high-energy radiation detection with bipolar charge transport.

[0044] ① Based on the Bridgman method growth technology, the present invention enhances the internal convection of the solute, optimizes the solid-liquid interface morphology, and effectively releases the latent heat of crystallization by introducing the crucible accelerated rotation technology (ACRT), reducing the thermal stress during crystal growth; adopting the segmented slow cooling technology and introducing in-situ annealing can effectively avoid or eliminate the internal stress caused by structural phase transformation, so as to realize the stable and controllable growth of large-size and high-quality halide semiconductor crystals for radiation detection.

[0045] ②Before crystal growth of the present invention, the zone melting purification technology is used to pre-treat the perovskite raw materials, significantly reducing the impurity concentration and avoiding the formation of secondary phases caused by deviation from the stoichiometric ratio. At the same time, the application of the crucible acceleration rotation technology further inhibits the formation of secondary phases, thereby optimizing the detector performance and improving the uniformity and crystal yield of the device.

[0046] ③The zone melting purification technology reduces the impurity concentration, and can simultaneously improve the hole and electron carrier transport properties in the halide perovskite crystal to ~10 -3 cm 2 V -1 or above, realizing bipolar charge transport. This improvement enables high-energy resolution detection with a detector based on a simple planar structure, improving the energy resolution of the 662 keV 137 Csγ ray to 2%, effectively avoiding complex device structure design.

[0047] The technical solution of the present invention has the following advantages compared with the prior art:

[0048] The present invention combines the Bridgman method with the zone melting purification technology, and grows a halide semiconductor single crystal for radiation detection by introducing the crucible acceleration rotation technology and the segmented slow cooling technology, realizing the stable and controllable preparation of a large-volume single crystal with high energy resolution for bipolar charge transport, and solving the following problems:

[0049] (1) The crucible acceleration rotation technology is beneficial to reducing the internal thermal stress of the crystal, and the combination of the segmented cooling process and in-situ annealing can effectively avoid the internal stress caused by structural phase transformation. These measures not only help prevent the generation of crystal cracks and improve the single crystal rate, but also create favorable conditions for the stable and controllable growth of large-size halide semiconductor crystals.

[0050] (2) The zone melting purification pretreatment can significantly reduce the impurity concentration and improve the crystal purity; the crucible acceleration rotation technology can effectively inhibit the formation of defects such as secondary phases, thereby improving the carrier transport performance, further improving the detector performance, and at the same time, this technology also significantly improves the uniformity and yield of the device, laying a solid foundation for the application of high-performance halide semiconductors for radiation detection.

[0051] (3) The zone melting purification treatment can simultaneously improve the hole and electron carrier transport properties in the halide perovskite crystal, realizing bipolar charge transport, enabling high-energy resolution detection with a detector based on a simple planar structure, making the detector design simpler, and contributing to the application and development of the detector in the field of radiation detection. Description of the Drawings

[0052] Figure 1 It is a physical picture of a large-size CsPbBr3 single crystal with a diameter of 54 mm and a length of 80 mm grown in Example 1.

[0053] Figure 2 Performance characterization diagram of the CsPbBr3 crystal in Example 1; among them, (a) is the mobility-lifetime product of holes and electrons in the CsPbBr3 crystal, and (b) is the 137 Cs γ-ray energy spectrum.

[0054] Figure 3 Physical diagram of a large-size CsPbBr3 single crystal with a diameter of 40 mm and a length of ~70 mm grown in Example 2. Detailed implementation manners

[0055] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and be able to implement it, but the exemplified embodiments are not intended to limit the present invention.

[0056] Example 1 Halide CsPbBr3

[0057] 1. Rinse the quartz crucible with deionized water for 5 min, then immerse it in an acetone solution for 15 h to remove residual organic substances on the crucible wall, etc.; then rinse it with deionized water for 5 min, and immerse it in aqua regia (concentrated hydrochloric acid: concentrated nitric acid = 3:1) for 24 h to remove other impurities on the crucible wall; finally, rinse it with deionized water for 5 min and place it in an oven to dry at 130 °C for 15 h to remove residual moisture on the crucible wall;

[0058] 2. In order to reduce the influence of impurity elements, CsBr and PbBr2 with a purity ≥ 4N (99.99%) are selected as the initial raw materials; when weighing the raw materials, in order to avoid the influence of water and oxygen in the air, the weighing is carried out in a dry glove box, and the CsBr and PbBr2 raw materials are weighed strictly according to a molar ratio of 1:1; put them into the quartz crucible treated in step 1, and then evacuate the quartz crucible to below 4.8×10 -4 Pa, and use a hydrogen-oxygen flame for welding and sealing;

[0059] 3. Place the quartz crucible welded and sealed in step 2 in a two-temperature-zone tube furnace, and heat it to 350 °C within 8 h, keep it warm for 4 h, then slowly heat it to 600 °C at a rate of 10 °C / h, and keep it warm for 30 h for CsPbBr3 polycrystalline material synthesis; finally, cool it to room temperature within 12 h to obtain a quartz crucible containing CsPbBr3 polycrystalline material;

[0060] 4. Place the quartz crucible obtained in Step 3 above into a three-zone furnace. Heat the three heaters to 600 °C, 570 °C, and 600 °C respectively and keep them at these temperatures for 10 h. Subsequently, move the three-zone heater from one end of the quartz crucible at a rate of 30 mm / h until it passes through the entire quartz crucible. Then quickly move the three-zone heater back to the initial position for the next zone melting process. After 5 cycles, a zone-melted CsPbBr3 polycrystalline ingot is obtained.

[0061] 5. Remove the front one-third and the tail one-third of multiple zone-melted CsPbBr3 polycrystalline ingots obtained in Step 4 above, and only retain the middle one-third region of the polycrystalline ingots. Select a total of 580 g from the middle one-third regions of multiple zone-melted polycrystalline ingots, crush them and reload them into the quartz crucible treated in Step 1. Evacuate to below 4.6×10 -4 Pa, and use an oxy-hydrogen flame for welding and sealing.

[0062] 6. Repeat the experiment in Step 3 for the quartz crucible welded and sealed in Step 5 above to obtain a quartz crucible filled with zone-melted CsPbBr3 polycrystalline material.

[0063] 7. Place the quartz crucible obtained in Step 6 above into a four-zone Bridgman crystal growth furnace. Heat it to the programmed temperature within 10 h. The set temperatures for the four zones are 620 °C, 650 °C, 450 °C, and 420 °C respectively. Subsequently, move the crucible so that its lowest end is at 600 °C and superheat for 24 h to ensure that the polycrystalline material in the crucible is completely melted and homogenized.

[0064] 8. Slowly lower the quartz crucible superheated in Step 7 above so that the temperature at its lowest end is 571 °C. After keeping it at this temperature for 4 h, turn on the ACRT rotation control system. The control parameters of ACRT are: accelerate from 0 r / min to 15 r / min in the positive direction in 5 s, rotate at a constant speed for 15 s, then decelerate to 0 r / min in 5 s and keep it for 10 s. Subsequently, accelerate from 0 r / min to 15 r / min in the reverse direction in 5 s, rotate at a constant speed for 15 s, then decelerate to 0 r / min in 5 s and keep it for 10 s. At the same time, lower the quartz crucible at a rate of 0.5 mm / h to grow CsPbBr3 crystals. After growing for 180 h, stop lowering the crucible and turn off the ACRT rotation control system.

[0065] 9. Cool down the four-zone Bridgman furnace after crystal growth in Step 8 above. Slowly cool the four zones to 400 °C simultaneously within 72 h, keep it at this temperature for 15 h for in-situ annealing to eliminate stress. Then cool it at a rate of 20 °C / h to 150 °C and keep it for 4 h. Then slowly cool it to room temperature at a rate of 5 °C / h, turn off the power supply, take out the quartz crucible, and the crystal growth is completed.

[0066] The CsPbBr3 single crystal grown in this example has a diameter of 54 mm and a length of ~80 mm. As Figure 1 shown, the crystal has good crystallization quality and an impurity concentration of about 6.16 ppm. For specific detector performance tests, the hole and electron mobility-lifetime products are 6.07×10 -3 cm 2 V -1 and 3.34×10 -3 cm 2 V -1 respectively. As Figure 2 shown, based on planar devices, the energy resolution for 662 keV 137 Csγ rays can reach 1.6%, 1.5%, 1.8% or 1.3%, demonstrating excellent device uniformity.

[0067] Example 2 Halide CsPbBr3

[0068] 1. Rinse the quartz crucible with deionized water for 5 min, then soak it in acetone solution for 12 h to remove residual organic matter on the crucible wall, etc.; after rinsing with deionized water for 5 min again, soak it in aqua regia (concentrated hydrochloric acid: concentrated nitric acid = 3:1) for 24 h to remove other impurities on the crucible wall; finally, rinse it with deionized water for 5 min and place it in an oven to dry at 125 °C for 24 h to remove residual moisture on the crucible wall;

[0069] 2. To reduce the influence of impurity elements, CsBr and PbBr2 with a purity ≥4N (99.99%) are selected as the initial raw materials; when weighing the raw materials, in order to avoid the influence of water and oxygen in the air, the weighing is carried out in a dry glove box, and the CsBr and PbBr2 raw materials are weighed strictly according to a molar ratio of 1:1; load them into the quartz crucible treated in step 1, and then evacuate the quartz crucible to below 4.2×10 -4 Pa and seal it with a hydrogen-oxygen flame;

[0070] 3. Place the quartz crucible sealed in step 2 in a two-temperature-zone tube furnace, heat it to 350 °C within 6 h, keep it warm for 2 h, then slowly heat it to 600 °C at a rate of 15 °C / h, and keep it warm for 24 h for CsPbBr3 polycrystalline material synthesis; finally, cool it to room temperature within 12 h to obtain a quartz crucible containing CsPbBr3 polycrystalline material;

[0071] 4. Place the quartz crucible obtained in Step 3 above in a three-zone furnace, and heat the three heaters to 595 °C, 570 °C, and 590 °C respectively within 10 h for heat preservation; then move the three-zone heater from one end of the quartz crucible at a rate of 20 mm / h until it passes through the entire quartz crucible; then quickly move the three-zone heater back to the initial position for the next zone melting process. After 3 cycles, the zone-melted CsPbBr3 polycrystalline ingot is obtained.

[0072] 5. Remove the front one-third and the tail one-third of multiple zone-melted CsPbBr3 polycrystalline ingots obtained in Step 4 above, and only retain the middle one-third region of the polycrystalline ingots; select a total of 400 g from the middle one-third regions of multiple zone-melted polycrystalline ingots, crush them and reload them into the quartz crucible treated in Step 1, evacuate to below 4.5×10 -4 Pa, and use a hydrogen-oxygen flame for welding and sealing.

[0073] 6. Repeat the experiment in Step 3 for the quartz crucible welded and sealed in Step 5 above to obtain a quartz crucible filled with zone-melted CsPbBr3 polycrystalline material.

[0074] 7. Place the quartz crucible obtained in Step 6 above in a four-zone Bridgman crystal growth furnace, heat it to the programmed temperature within 12 h, and the set temperatures of the four zones are 620 °C, 650 °C, 450 °C, and 420 °C respectively. Then move the crucible so that its lowest end is at 600 °C and superheat for 30 h to ensure that the polycrystalline material in the crucible is completely melted and homogenized.

[0075] 8. Slowly lower the quartz crucible superheated in Step 7 above so that the temperature of its lowest end is at 573 °C. After heat preservation for 4 h, turn on the ACRT rotation control system. The control parameters of ACRT are: accelerate from 0 r / min to 20 r / min in the positive direction in 5 s, rotate at a constant speed for 20 s, then decelerate to 0 r / min in 5 s and hold for 20 s; then accelerate from 0 r / min to 20 r / min in the reverse direction in 5 s, rotate at a constant speed for 20 s, then decelerate to 0 r / min in 5 s and hold for 20 s; at the same time, the quartz crucible descends at a rate of 0.5 mm / h for CsPbBr3 crystal growth. After growing for 140 h, the crucible stops descending and the ACRT rotation control system is turned off.

[0076] 9. Cool down the four-zone Bridgman furnace after growth in Step 8 above. Slowly cool the four zones to 400 °C simultaneously within 70 h, keep warm for 24 h for in-situ annealing to eliminate stress; then cool down at a rate of 15 °C / h to 150 °C simultaneously and keep warm for 8 h; then slowly cool to room temperature at a rate of 3 °C / h, turn off the power supply, take out the quartz crucible, and the crystal growth is completed.

[0077] In this embodiment, CsPbBr3 single crystals with a diameter of 40 mm and a length of ~70 mm are grown. As Figure 3 shown, the product of the hole and electron mobility lifetimes are 7.28×10 -3 cm 2 V -1 and 2.84×10 -3 cm 2 V -1 , respectively. Based on planar devices, the energy resolutions for 662 keV 137 Csγ rays can reach 1.8%, 1.7%, 1.7% and 1.5%, demonstrating excellent device uniformity.

[0078] Example 3 Halide CsPbBr2Cl

[0079] 1. Rinse the quartz crucible with deionized water for 5 min, then soak it in acetone solution for 12 h to remove residual organic substances on the crucible wall, etc.; then rinse it with deionized water for 5 min, and soak it in aqua regia (concentrated hydrochloric acid: concentrated nitric acid = 3:1) for 15 h to remove other impurities on the crucible wall; finally, rinse it with deionized water for 5 min and place it in an oven to dry at 130 °C for 12 h to remove residual moisture on the crucible wall;

[0080] 2. To reduce the influence of impurity elements, CsBr and PbBr2 with a purity of ≥4N (99.99%) are selected as the initial raw materials; when weighing the raw materials, in order to avoid the influence of water and oxygen in the air, the weighing is carried out in a dry glove box, and the CsBr and PbBr2 raw materials are weighed strictly according to a molar ratio of 1:1; load them into the quartz crucible treated in step 1, and then evacuate the quartz crucible to below 4.7×10 -4 Pa and seal it with a hydrogen-oxygen flame;

[0081] 3. Place the quartz crucible sealed in step 2 in a two-temperature zone tube furnace, and heat it to 350 °C within 6 h, keep it warm for 2 h, then slowly heat it to 600 °C at a rate of 10 °C / h, and keep it warm for 24 h for CsPbBr3 polycrystalline material synthesis; finally, cool it to room temperature within 12 h to obtain a quartz crucible containing CsPbBr3 polycrystalline material;

[0082] 4. Place the quartz crucible obtained in step 3 above in a three-temperature zone zone melting furnace, heat the three-section heaters to 590 °C, 570 °C, and 590 °C respectively and keep them warm within 8 h; then move the three-temperature zone heater from one end of the quartz crucible at a rate of 30 mm / h until it passes through the entire quartz crucible; then quickly move the three-temperature zone heater back to the initial position for the next zone melting process. After 5 cycles, the zone-melted CsPbBr3 polycrystalline ingot is obtained;

[0083] 5. Select CsCl and PbCl2 with a purity ≥ 4N (99.99%) as the initial raw materials; when weighing the raw materials, in order to avoid the influence of water, oxygen, etc. in the air, weigh them in a dry glove box and strictly weigh the CsCl and PbCl2 raw materials according to a molar ratio of 1:1; put them into the quartz crucible treated in step 1, and then evacuate the quartz crucible to below 4.8×10 -4 Pa, and seal it with a hydrogen-oxygen flame;

[0084] 6. Place the quartz crucible sealed in step 5 in a two-temperature-zone tube furnace, and heat it to 400 °C within 10 h, keep it warm for 4 h, then slowly heat it to 650 °C at a rate of 10 °C / h, and keep it warm for 30 h for the synthesis of CsPbCl3 polycrystalline material; finally, cool it to room temperature within 12 h to obtain a quartz crucible containing CsPbCl3 polycrystalline material;

[0085] 7. Place the quartz crucible obtained in step 6 above in a three-temperature-zone zone melting furnace, heat the three heaters to 650 °C, 620 °C, and 650 °C respectively and keep them warm within 10 h; then move the three-temperature-zone heater from one end of the quartz crucible at a rate of 40 mm / h until it passes through the entire quartz crucible; then quickly move the three-temperature-zone heater back to the initial position for the next zone melting process. After 5 cycles, obtain a zone-melted CsPbCl3 polycrystalline ingot;

[0086] 8. Remove the front one-third and the tail one-third of the zone-melted CsPbBr3 and CsPbCl3 polycrystalline ingots obtained in steps 4 and 7 above, and only retain the middle one-third area of the polycrystalline ingot; select a total of ~150 g from the middle one-third areas of multiple CsPbBr3 and CsPbCl3 zone-melted polycrystalline ingots, crush them and reload them into the quartz crucible treated in step 1 according to the molar ratio CsPbBr3:CsPbCl3 = 2:1, evacuate to below 4.1×10 -4 Pa, and seal it with a hydrogen-oxygen flame;

[0087] 9. Place the quartz crucible sealed in step 8 above in a two-temperature-zone tube furnace, and heat it to 350 °C within 10 h, keep it warm for 2 h, then slowly heat it to 600 °C at a rate of 10 °C / h, and keep it warm for 30 h for the synthesis of CsPbBr2Cl polycrystalline material; finally, cool it to room temperature within 12 h to obtain a quartz crucible containing CsPbBr2Cl polycrystalline material;

[0088] 10. Place the quartz crucible obtained in step 9 above in a four-temperature-zone Bridgman crystal growth furnace, heat it to the program-set temperature within 12 h, and the set temperatures of the four temperature zones are 600 °C, 620 °C, 420 °C, and 400 °C respectively. Then move the crucible so that its lowest end is at 550 °C and superheat for 24 h to ensure that the polycrystalline material in the crucible is completely melted and homogenized;

[0089] 11. Slowly lower the quartz crucible after overheating in Step 10 above so that the temperature at its lowest end is 535 °C. After heat preservation for 4 h, turn on the ACRT rotation control system. The control parameters of ACRT are as follows: Accelerate forward from 0 r / min to 20 r / min in 5 s, rotate at a constant speed for 20 s, then decelerate to 0 r / min in 5 s and maintain for 20 s; subsequently, accelerate backward from 0 r / min to 20 r / min in 5 s, rotate at a constant speed for 20 s, then decelerate to 0 r / min in 5 s and maintain for 20 s; at the same time, the quartz crucible descends at a rate of 0.5 mm / h to grow CsPbBr2Cl crystals. After growing for 140 h, the crucible stops descending and the ACRT rotation control system is turned off.

[0090] 12. Cool down the four-zone Bridgman furnace after growth in Step 11 above. Slowly cool the four zones to 350 °C simultaneously within 60 h and keep it at this temperature for 24 h; then cool it at a rate of 15 °C / h to 150 °C simultaneously and keep it at this temperature for 8 h; then slowly cool it to room temperature at a rate of 3 °C / h, turn off the power supply, take out the quartz crucible, and the crystal growth is completed.

[0091] In this example, a CsPbBr2Cl single crystal with a diameter of 30 mm and a length of ∼60 mm is grown. The crystal has good crystallization quality. During specific device testing, the product of the hole and electron mobility lifetimes is 5.12×10 -3 cm 2 V -1 and 2.57×10 -3 cm 2 V -1 , respectively. Based on planar devices, the energy resolution for 662 keV 137 Csγ rays can reach 2.0% or 1.8%, and the device uniformity is relatively good. Example 4 Halide Cs 0.9 Rb 0.1 PbBr 2.7 Cl 0.3

[0092] 1. Rinse the quartz crucible with deionized water for 10 min, then immerse it in an acetone solution for 15 h to remove residual organic substances on the crucible wall, etc.; then rinse it with deionized water for 10 min and immerse it in aqua regia (concentrated hydrochloric acid: concentrated nitric acid = 3:1) for 24 h to remove other impurities on the crucible wall; finally, rinse it with deionized water for 10 min and place it in an oven to dry at 130 °C for 15 h to remove residual moisture on the crucible wall.

[0093] 2. To reduce the influence of impurity elements, CsBr and PbBr2 with a purity ≥ 4N (99.99%) are selected as the initial raw materials. When weighing the raw materials, to avoid the influence of water and oxygen in the air, the weighing is carried out in a dry glove box, and the CsBr and PbBr2 raw materials are weighed strictly according to a 1:1 molar ratio. They are loaded into the quartz crucible treated in step 1, and then the quartz crucible is evacuated to below 4.5×10 -4 Pa, and welded and sealed using a hydrogen-oxygen flame;

[0094] 3. The quartz crucible welded and sealed in step 2 is placed in a two-temperature zone tube furnace, and heated to 350 °C within 8 h, held for 2 h, and then slowly heated to 600 °C at a rate of 20 °C / h, and held for 24 h for the synthesis of CsPbBr3 polycrystalline material. Finally, it is cooled to room temperature within 12 h to obtain a quartz crucible containing CsPbBr3 polycrystalline material;

[0095] 4. The quartz crucible obtained in step 3 above is placed in a three-temperature zone zone melting furnace, and the three-section heaters are heated to 600 °C, 580 °C, and 605 °C respectively and held for 10 h. Subsequently, the three-temperature zone heater is moved from one end of the quartz crucible at a rate of 25 mm / h until it passes through the entire quartz crucible. Then the three-temperature zone heater is quickly moved back to the initial position for the next zone melting process. After 4 cycles, the zone-melted CsPbBr3 polycrystalline ingot is obtained;

[0096] 5. RbCl and PbCl2 with a purity ≥ 4N (99.99%) are selected as the initial raw materials. When weighing the raw materials, to avoid the influence of water and oxygen in the air, the weighing is carried out in a dry glove box, and the RbCl and PbCl2 raw materials are weighed strictly according to a 1:1 molar ratio. They are loaded into the quartz crucible treated in step 1, and then the quartz crucible is evacuated to below 4.9×10 -4 Pa, and welded and sealed using a hydrogen-oxygen flame;

[0097] 6. The quartz crucible welded and sealed in step 5 is placed in a two-temperature zone tube furnace, and heated to 300 °C within 10 h, held for 6 h, and then slowly heated to 580 °C at a rate of 10 °C / h, and held for 24 h for the synthesis of RbPbCl polycrystalline material. Finally, it is cooled to room temperature within 12 h to obtain a quartz crucible containing RbPbCl3 polycrystalline material;

[0098] 7. The quartz crucible obtained in step 6 above is placed in a three-temperature zone zone melting furnace, and the three-section heaters are heated to 460 °C, 450 °C, and 460 °C respectively and held for 10 h. Subsequently, the three-temperature zone heater is moved from one end of the quartz crucible at a rate of 30 mm / h until it passes through the entire quartz crucible. Then the three-temperature zone heater is quickly moved back to the initial position for the next zone melting process. After 5 cycles, the zone-melted RbPbCl3 polycrystalline ingot is obtained;

[0099] 8. Remove the front one-third and the tail one-third of the zone-melted polycrystalline ingots of CsPbBr3 and RbPbCl3 obtained in the above steps 4 and 7, and only retain the middle one-third region of the polycrystalline ingots; Select a total of ~120 g from the middle one-third regions of multiple CsPbBr3 and RbPbCl3 zone-melted polycrystalline ingots, crush them and reload them into the quartz crucible treated in step 1 according to the molar ratio CsPbBr3:RbPbCl3 = 9:1, and evacuate to below 4.3×10 -4 Pa, and use a hydrogen-oxygen flame for welding and sealing;

[0100] 9. Place the quartz crucible welded and sealed in the above step 8 into a two-temperature-zone tube furnace, and heat it to 300 °C within 12 h. After holding for 2 h, slowly heat it to 580 °C at a rate of 15 °C / h, and hold for 24 h for Cs 0.9 Rb 0.1 PbBr 2.7 Cl 0.3 polycrystalline material synthesis; Finally, cool it to room temperature within 12 h to obtain a quartz crucible containing Cs 0.9 Rb 0.1 PbBr 2.7 Cl 0.3 polycrystalline material;

[0101] 10. Place the quartz crucible obtained in the above step 9 into a four-temperature-zone Bridgman crystal growth furnace, heat it to the program-set temperature within 10 h, and the set temperatures of the four temperature zones are 580 °C, 610 °C, 400 °C, and 350 °C respectively. Then move the crucible so that its lowest end is at 585 °C and superheat for 24 h to ensure that the polycrystalline material in the crucible is completely melted and homogenized;

[0102] 11. Slowly lower the quartz crucible superheated in the above step 10 so that the temperature of its lowest end is at 570 °C. After holding for 4 h, turn on the ACRT rotation control system. The control parameters of ACRT are: accelerate from 0 r / min to 15 r / min in 5 s, rotate at a constant speed for 20 s, then decelerate to 0 r / min in 5 s and hold for 20 s; then accelerate from 0 r / min to 15 r / min in 5 s in the reverse direction, rotate at a constant speed for 20 s, and then decelerate to 0 r / min in 5 s and hold for 20 s; At the same time, the quartz crucible descends at a rate of 0.5 mm / h for Cs 0.9 Rb 0.1 PbBr 2.7 Cl 0.3 crystal growth. After growing for 120 h, the crucible stops descending and the ACRT rotation control system is turned off;

[0103] 12. Cool down the Bridgman furnace with four temperature zones after the growth in step 11 above. Slowly cool down the four temperature zones to 350 °C simultaneously within 60 h, and keep the temperature for 24 h. Then cool down at a rate of 10 °C / h to 150 °C simultaneously, and keep the temperature for 8 h. Then slowly cool down to room temperature at a rate of 5 °C / h, turn off the power supply, take out the quartz crucible, and the crystal growth is completed.

[0104] In this example, Cs 0.9 Rb 0.1 PbBr 2.7 Cl 0.3 single crystals with a diameter of 25 mm and a length of ~50 mm are grown, and the mobility-lifetime products of holes and electrons are 3.24×10 -3 cm 2 V -1 and 1.43×10 -3 cm 2 V -1 , respectively. Based on planar devices, the energy resolution for 662 keV 137 Cs γ-rays can reach 1.9%.

[0105] Example 5 Halide CsPbBr 2.7 (SCN) 0.3

[0106] 1. Rinse the quartz crucible with deionized water for 10 min, then soak it in acetone solution for 12 h to remove residual organic substances on the crucible wall, etc. After rinsing with deionized water for 10 min again, soak it in aqua regia (concentrated hydrochloric acid: concentrated nitric acid = 3:1) for 30 h to remove other impurities on the crucible wall. Finally, rinse it with deionized water for 10 min and place it in an oven to dry at 135 °C for 12 h to remove residual moisture on the crucible wall.

[0107] 2. To reduce the influence of impurity elements, CsBr and PbBr2 with a purity of ≥4N (99.99%) are selected as the initial raw materials. When weighing the raw materials, to avoid the influence of water and oxygen in the air, the weighing is carried out in a dry glove box, and the CsBr and PbBr2 raw materials are weighed strictly according to a molar ratio of 1:1. Load them into the quartz crucible treated in step 1, then evacuate the quartz crucible to below 4.2×10 -4 Pa, and seal it with a hydrogen-oxygen flame.

[0108] 3. Place the quartz crucible sealed in step 2 into a two-temperature-zone tube furnace, and heat it to 320 °C within 10 h. After keeping the temperature for 4 h, slowly heat it to 600 °C at a rate of 20 °C / h, and keep the temperature for 24 h for CsPbBr3 polycrystalline material synthesis. Finally, cool it to room temperature within 12 h to obtain a quartz crucible containing CsPbBr3 polycrystalline material.

[0109] 4. Place the quartz crucible obtained in the above step 3 in a three-zone zone melting furnace, heat the three-section heaters to 600 °C, 580 °C, and 600 °C respectively within 10 h and keep them warm; then move the three-zone heater from one end of the quartz crucible at a rate of 30 mm / h until it passes through the entire quartz crucible; then quickly move the three-zone heater back to the initial position for the next zone melting process. After 3 cycles, the zone-melted CsPbBr3 polycrystalline ingot is obtained.

[0110] 5. Select CsBr and Pb(SCN)2 with a purity ≥ 4N (99.99%) as the initial raw materials; when weighing the raw materials, in order to avoid the influence of water and oxygen in the air, weigh them in a dry glove box and strictly weigh the CsBr and Pb(SCN)2 raw materials according to a molar ratio of 1:1; load them into the quartz crucible treated in step 1, and then evacuate the quartz crucible to below 4.7×10 -4 Pa, and use a hydrogen-oxygen flame for welding and sealing.

[0111] 6. Place the quartz crucible welded and sealed in step 5 in a two-zone tube furnace, heat it to 300 °C within 10 h, keep it warm for 6 h, then slowly heat it to 580 °C at a rate of 10 °C / h, and keep it warm for 24 h for the synthesis of CsPbBr2(SCN) polycrystalline material; finally, cool it to room temperature within 12 h to obtain a quartz crucible containing CsPbBr2(SCN) polycrystalline material.

[0112] 7. Place the quartz crucible obtained in the above step 6 in a three-zone zone melting furnace, heat the three-section heaters to 580 °C, 560 °C, and 585 °C respectively within 10 h and keep them warm; then move the three-zone heater from one end of the quartz crucible at a rate of 30 mm / h until it passes through the entire quartz crucible; then quickly move the three-zone heater back to the initial position for the next zone melting process. After 3 cycles, the zone-melted CsPbBr2(SCN) polycrystalline ingot is obtained.

[0113] 8. Remove the front one-third and the tail one-third of the zone-melted CsPbBr3 and CsPbBr2(SCN) polycrystalline ingots obtained in the above steps 4 and 7, and only retain the middle one-third region of the polycrystalline ingot; select a total of ~40 g from the middle one-third regions of multiple CsPbBr3 and CsPbBr2(SCN) zone-melted polycrystalline ingots, crush them and reload them into the quartz crucible treated in step 1 according to a molar ratio of CsPbBr3:CsPbBr2(SCN) = 7:3, evacuate it to below 4.4×10 -4 Pa, and use a hydrogen-oxygen flame for welding and sealing.

[0114] 9. Place the quartz crucible sealed in step 8 above in a two-temperature-zone tube furnace, and heat it to 300 °C within 12 h. After holding for 4 h, slowly heat it to 580 °C at a rate of 20 °C / h, and hold for 24 h for CsPbBr 2.7 (SCN) 0.3 polycrystalline material synthesis; finally, cool it to room temperature within 12 h to obtain a quartz crucible containing CsPbBr 2.7 (SCN) 0.3 polycrystalline material;

[0115] 10. Place the quartz crucible obtained in step 9 above in a four-temperature-zone Bridgman crystal growth furnace, heat it to the programmed temperature within 10 h. The set temperatures of the four temperature zones are 580 °C, 610 °C, 400 °C, and 350 °C respectively. Then move the crucible so that its lowest end is at 580 °C and superheat for 24 h to ensure that the polycrystalline material in the crucible is completely melted and homogenized;

[0116] 11. Slowly lower the quartz crucible superheated in step 10 above so that the temperature of its lowest end is at 572 °C. After holding for 6 h, turn on the ACRT rotation control system. The control parameters of ACRT are: accelerate from 0 r / min to 15 r / min in the positive direction in 5 s, rotate at a constant speed for 20 s, then decelerate to 0 r / min in 5 s and hold for 20 s; then accelerate from 0 r / min to 15 r / min in the reverse direction in 5 s, rotate at a constant speed for 20 s, and then decelerate to 0 r / min in 5 s and hold for 20 s; at the same time, the quartz crucible descends at a rate of 0.5 mm / h for CsPbBr 2.7 (SCN) 0.3 crystal growth. After growing for 140 h, the crucible stops descending and the ACRT rotation control system is turned off;

[0117] 12. Cool down the four-temperature-zone Bridgman furnace after growth in step 11 above. Slowly cool the four temperature zones to 350 °C simultaneously within 60 h and hold for 24 h; then cool at a rate of 10 °C / h simultaneously to 150 °C and hold for 8 h; then slowly cool to room temperature at a rate of 5 °C / h, turn off the power supply, take out the quartz crucible, and the crystal growth is completed.

[0118] In this example, a CsPbBr single crystal with a diameter of 15 mm and a length of ~60 mm is grown, and the mobility-lifetime products of holes and electrons are 3.48×10 2.7 (SCN) 0.3 respectively. Based on planar devices for 662 keV of -3 cm 2 V -1 and 1.21×10 -3 cm 2 V -1 , based on planar devices for 662 keV of 137The energy resolution of Csγ rays can reach 2.0%.

[0119] Effect evaluation 1

[0120] The present invention discloses a preparation method of a halide semiconductor single crystal with bipolar charge transport for high-energy radiation detection. By using the crucible accelerated rotation technology, the segmented slow cooling technology and in-situ annealing, the generation of cracks in the crystal is effectively avoided, and a large-volume single crystal of high quality is obtained. The zone melting purification technology is used to improve the purity of the crystal and avoid the generation of secondary phases, which is beneficial to improving the hole carrier transport performance of the perovskite crystal, thereby improving the device uniformity and crystal yield, and realizing high-energy resolution detection. At the same time, the zone melting purification technology is beneficial to improving the electron carrier transport performance, realizing bipolar charge transport, and simplifying the device structure of the detector.

[0121] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A preparation method of a halide semiconductor single crystal with bipolar charge transport for high-energy radiation detection, characterized in that, It includes the following steps: S11: Load CsBr and PbBr2 into a crucible and seal it by soldering; S12: In a tube furnace, keep the crucible at 570 - 650 °C for 24 - 36 h, cool it to room temperature, and then perform 1 - 20 zone melting cycles at 570 - 620 °C to obtain a CsPbBr3 polycrystalline ingot; S13: Heat the crucible containing the CsPbBr3 polycrystalline ingot in a crystal growth furnace and then perform downward heat preservation; the crucible may or may not contain an ABX3 polycrystalline ingot, and the ABX3 polycrystalline ingot is obtained by AX and BX2 according to the methods of steps S11 and S12; S14: Use the vertical Bridgman method to grow a halide semiconductor crystal in the crucible for 100 - 600 h; S15: Cool the crucible to 300 - 400 °C in 48 - 72 h and perform heat preservation annealing for 12 - 24 h; S16: After cooling the crucible, take out the product to obtain the halide semiconductor single crystal; The chemical formula of the halide semiconductor single crystal is Cs 1-x A x Pb 1-y B y Br 3-z X z , where A is selected from one or more of Na, K, Rb, Cu, Tl, and H3O, B is selected from one or more of Si, Ge, Sn, Mg, Ca, Sr, Ba, Zn, Cd, and Hg, X is selected from one or more of F, Cl, I, BF4, HCOO, OH, CN, SCN, NCS, SH, NO3, and H2POO, and 0 ≤ x ≤ 1, 0 ≤ y ≤ 1, 0 ≤ z ≤ 3.

2. The preparation method according to claim 1, wherein In the step S12, the preparation method of the CsPbBr3 polycrystalline ingot includes the following steps: S21: In a tube furnace, heat the crucible to 250 - 400 °C within 6 - 12 h and keep it for 2 - 4 h; S22: Heat the crucible at a rate of 10 - 20 °C / h to 570 - 650 °C and keep it for 24 - 36 h for polycrystalline material synthesis; S23: Cool the crucible to room temperature within 10 - 12 h and then perform 1 - 20 zone melting cycles in a furnace at 570 - 620 °C to obtain a CsPbBr3 polycrystalline ingot.

3. The preparation method according to claim 1, characterized in that, In the step S12, the zone melting cycle uses a three - temperature - zone furnace. The method is to move the heater from one end of the crucible to the other end at a rate of 5 - 100 mm / h until it passes through the entire crucible, and then move the heater back to the initial position for the next zone melting process.

4. The preparation method according to claim 1, characterized in that, In the step S13, the crucible containing the CsPbBr3 polycrystalline ingot is obtained by crushing the CsPbBr3 polycrystalline ingot after removing the front end and the tail end, re - adding it to the crucible, and then vacuum - sealing it.

5. The preparation method according to claim 1, characterized in that, In the step S13, during overheating, the bottom of the crucible is at 550 - 650 °C for 24 - 36 h; during heat preservation, the bottom of the crucible is at 500 - 600 °C and heat - preserved for 4 - 6 h.

6. The preparation method according to claim 1, characterized in that, In the step S14, during the growth of the halide semiconductor crystal, the crucible acceleration rotation technology control system is used to alternately perform forward and reverse rotations, and at the same time, it descends at a rate of 0.1 - 10 mm / h.

7. The preparation method according to claim 6, characterized in that, The method of alternately performing forward and reverse rotations is to accelerate from 0 r / min to 1 - 50 r / min in 1 - 30 s, rotate at a constant speed for 0 - 50 s, then decelerate to 0 r / min in 1 - 30 s and keep it for 0 - 50 s; then accelerate from 0 r / min to 1 - 50 r / min in 1 - 30 s, rotate at a constant speed for 0 - 50 s, and then decelerate to 0 r / min in 1 - 30 s and keep it for 0 - 50 s.

8. The preparation method according to claim 1, characterized in that, In the step S16, the cooling method is: cool it to 150 - 200 °C at a rate of 15 - 30 °C / h and keep it for 4 - 8 h; then slowly cool it to room temperature at a rate of 3 - 5 °C / h.

9. A halide semiconductor single crystal with bipolar charge transport for high-energy radiation detection prepared by the preparation method according to any one of claims 1-8, characterized in that, The chemical formula of the halide semiconductor single crystal is Cs 1-x A x Pb 1- y B y Br 3-z X z , where A is selected from one or more of Na, K, Rb, Cu, Tl, and H3O, B is selected from one or more of Si, Ge, Sn, Mg, Ca, Sr, Ba, Zn, Cd, and Hg, X is selected from one or more of F, Cl, I, BF4, HCOO, OH, CN, SCN, NCS, SH, NO3, and H2POO, and 0 ≤ x ≤ 1, 0 ≤ y ≤ 1, 0 ≤ z ≤ 3.

10. A nuclear radiation detector, characterized in that, Use the halide semiconductor single crystal with bipolar charge transport for high-energy radiation detection described in claim 9.

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