Application of ferroelectric ceramic material in self-driven X-ray detection

Abstract

The invention belongs to the field of X-ray detection, and particularly relates to application of a ferroelectric ceramic material in self-driven X-ray detection. An X-ray detector adopted for self-driven X-ray detection is of a semiconductor detector structure, a detection medium in the semiconductor detector structure is the ferroelectric ceramic material, the ferroelectric ceramic material is one or more of Pb (ZrxTi1-x) O3, Pb (Zr, Ti) O3, Mn, BaTiO3, BiGaO3, Bi4Ti3O12, Bi4Ge3O12, SrxBa (1-x) Nb2O6 and Pb (Mg1 / 3Nb2 / 3) (1-x) TixO3, and x is larger than or equal to 0 and smaller than or equal to 1. The ferroelectric ceramic material is directly used for preparing the high-temperature self-driven X-ray detector of a semiconductor detector structure, high-temperature X-ray imaging can be achieved, imaging is clear, and the high-temperature self-driven X-ray detector has the advantages of being simple in preparation process, low in cost and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of X-ray detection, and particularly relates to an application of a ferroelectric ceramic material in self-driven X-ray detection. BACKGROUND

[0002] The information disclosed in this Background section is for the purpose of generally presenting the context of the application. The information disclosed in this Background section is not to be taken as an acknowledgement or any form of suggestion that it forms prior art merely by virtue of its disclosure.

[0003] It is well known that X-ray radiation has serious harm to health. The innovation of X-ray detection technology has always been closely related to the breakthrough of material systems. Therefore, X-ray detectors combining ultra-low detection limit and high sensitivity have obtained great research interest. In order to obtain better detection materials than commercial α-Se, Cd 0.9 Zn 0.1 Te (CZT), and CdTe crystals, a variety of materials such as halide perovskite (such as MAPbI3, CsPbBr3, and Cs2AgBiBr6), oxide crystals (such as β -Ga2O3, BaTeW2O9, Li2ZrTeO6, ZrTe3O8, and SnTe3O8) and glass materials (such as α-Sb2S3, LASNG:Tb 3+ , and ZnPIm MOF glass) have been widely studied.

[0004] Halide perovskite materials exhibit excellent detection performance in X-ray detector applications, but their poor environmental stability and thermal stability limit their use in extreme environments. Oxide crystal materials have the advantages of high resistivity, good thermal stability, and ultra-low detection limit, however, growing high-quality, large-size oxide single crystals faces major challenges. Glass materials, although have the advantages of low cost, element tunable, large-area preparation and simple process, etc., but their X-ray detection sensitivity is usually low, and it is difficult to apply to self-driven X-ray detector devices.

[0005] Self-driven X-ray detectors can work without external bias, have the advantages of low power consumption, strong portability, etc., and are an ideal solution to meet the needs of device miniaturization. Therefore, it is urgent to develop X-ray detection materials that combine the excellent performance of crystal materials and the easy processing characteristics of glass materials. SUMMARY

[0006] In order to solve the problems of the prior art, the application aims to provide an application of ferroelectric ceramic material in self-driven X-ray detection, and the application directly uses the ferroelectric ceramic material to prepare a high-temperature self-driven X-ray detector with a semiconductor detector structure, so that high-temperature X-ray imaging can be realized, the imaging is clear, and the application has the advantages of simple preparation process and low cost.

[0007] In order to achieve the above object, the technical scheme of the application is as follows: In a first aspect, the application relates to an application of ferroelectric ceramic material in preparing a self-driven X-ray detector or self-driven X-ray detection, wherein the X-ray detector used in the self-driven X-ray detector or self-driven X-ray detection is a semiconductor detector structure, the detection medium in the semiconductor detector structure is the ferroelectric ceramic material, and the ferroelectric ceramic material is one or more of Pb(Zr x Ti 1-x )O3, Pb(Zr,Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 12 , Bi4Ge3O 12 , Sr x Ba 1-x Nb2O6, Pb(Mg 1 / Nb 2 / 3 ) 1-x Ti x O3, and 0<=x<=1.

[0008] The application researches and finds that the ferroelectric ceramic material can be used to replace semiconductor material to prepare an X-ray detector with a semiconductor detector structure, and self-driven X-ray detection and self-driven X-ray imaging can be realized. The ferroelectric ceramic material has the advantages of controllable shape, large-area preparation, and simple preparation process, so that the operation difficulty and cost of the X-ray detector with a semiconductor detector structure are reduced.

[0009] In a second aspect, a high-temperature self-driven X-ray detector has a semiconductor detector structure and comprises a detection medium layer, wherein two opposite sides of the detection medium layer are respectively provided with a positive electrode layer and a negative electrode layer; the material of the detection medium layer is the ferroelectric ceramic material, and the ferroelectric ceramic material is one or more of Pb(Zr x Ti 1-x )O3, Pb(Zr,Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 12 , Bi4Ge3O 12 , Sr x Ba 1-x Nb2O6, Pb(Mg 1 / 3 Nb 2 / 3 ) 1-x Ti xone or more of O3, 0≤x≤1.

[0010] In a third aspect, an X-ray detection imaging system comprises: an X-ray source for emitting X-rays towards an object to be measured; an X-ray detector for receiving X-rays from the X-ray source or passing through the object to be measured and converting the X-rays into electrical signals; the X-ray detector is the self-driven high-temperature X-ray detector of the second aspect of the application; an imaging device for converting the electrical signals from the X-ray detector into image information.

[0011] wherein the X-rays emitted by the X-ray source are directed towards the X-ray detector and the object to be measured is arranged in the path of the X-rays from the X-ray source to the X-ray detector.

[0012] The present application has the following advantages 1. Self-driven high-temperature imaging capability: The X-ray detector of the present application adopts a vertical geometry (the imaging object is placed between the X-ray source and the X-ray detector). Ferroelectric ceramics (especially PZT ceramics) not only have controllable shape, easy large-area preparation, simple process, but also have excellent high-temperature stability. By adjusting the temperature and the applied electric field, a strong electrostatic field can be formed inside the material, which serves as the detection medium of the X-ray detector and is the key design to realize the self-driven X-ray detector. This is the first time that a ferroelectric ceramic (especially PZT ceramic) based X-ray detector has realized imaging function in a self-driven mode, significantly expanding its application scenarios.

[0013] 2. Simple and efficient device preparation: By sputtering positive and negative electrodes on the upper and lower surfaces of the ferroelectric ceramic (especially PZT ceramic), the preparation of the X-ray detector can be completed. This process effectively improves the carrier migration performance, while greatly simplifying the manufacturing process and reducing the cost.

[0014] 3. Excellent detection performance: Ferroelectric ceramics (especially PZT ceramics) have high resistivity, high X-ray absorption coefficient, high mobility-lifetime product, and low dark current drift, etc. The X-ray detector prepared based on this shows high sensitivity, ultra-low detection limit and extremely high running stability.

[0015] 4. Excellent material properties and scalability: Ferroelectric ceramics (especially PZT ceramics) are easy to realize large-area, high-quality and low-cost preparation. Their physical and chemical properties are stable, not easy to deliquesce, and can maintain stable performance in high-temperature environment, providing a foundation for reliable application of the detector. BRIEF DESCRIPTION OF DRAWINGS

[0016] The accompanying drawings, which form a part of this specification, are included to provide a further understanding of the application and are incorporated herein for explanation.

[0017] Figure 1 Optical photos and XRD patterns of PZT ceramics prepared in embodiments 1-3 of the present application, wherein a is an optical photo of PZT ceramics, b is a comparison chart of XRD pattern of PZT ceramics and a theoretical pattern; Figure 2 A structural schematic diagram of an X-ray detector based on lead zirconate titanate PZT ceramics of the present application, a is a structural schematic diagram, b is a schematic diagram of a photoelectric process of an Au / PZT / Au device of the present application under X-ray radiation, and c is a photoconductive gain; Figure 3 X-ray absorption coefficients of PZT ceramics prepared in embodiments 1-3 of the present application; Figure 4 Resistances of PZT ceramics prepared in embodiments 1-3 of the present application; Figure 5 Carrier mobility lifetime products of PZT ceramics prepared in embodiments 1-3 of the present application; Figure 6 Photocurrent curves of X-ray detectors based on lead zirconate titanate PZT ceramics prepared in embodiments 1-3 of the present application under different doses; wherein a is a photocurrent curve of a PZT ceramic X-ray detector under a 40 keV, 1000 V bias voltage; b is a photocurrent curve of a PZT ceramic X-ray detector under a 70 keV, 1000 V bias voltage; and c is a photocurrent curve of a PZT ceramic X-ray detector under a 120 keV, 1000 V bias voltage; Figure 7 Sensitivity test charts of X-ray detectors based on lead zirconate titanate PZT ceramics prepared in embodiments 1-3 of the present application; Figure 8 Photocurrent curves of self-driven X-ray detectors based on lead zirconate titanate PZT ceramics prepared in embodiments 1-3 of the present application under different doses, different temperatures and 0 V external bias voltage; wherein a-e are photocurrent curves of PZT ceramic self-driven X-ray detectors under 40, 70, 120 keV and 0 V bias voltage at 25℃ (a), 75℃ (b), 125℃ (c), 175℃ (d) and 255℃ (e), respectively; Figure 9 Sensitivity test charts of self-driven X-ray detectors based on lead zirconate titanate PZT ceramics prepared in embodiments 1-3 of the present application under different doses and different temperatures; Figure 10The detection limit test diagram of the X-ray detector based on the lead zirconate titanate PZT ceramic prepared in the embodiments 1-3 of the present application, wherein a is the detection limit test diagram of the X-ray detector of the PZT ceramic under different X-ray energies when the applied voltage is 1000 V; b is the detection limit test diagram of the self-driven X-ray detector of the PZT ceramic at 125 DEG C when the applied voltage is 0 V; Figure 11 The dark current drift curve of the X-ray detector based on the lead zirconate titanate PZT ceramic prepared in the embodiments 1-3 of the present application; Figure 12 The structure schematic diagram of the X-ray detection imaging based on the lead zirconate titanate PZT ceramic of the present application, wherein a is the schematic diagram of the X-ray imaging system of the PZT ceramic array X-ray detector; b is the PZT ceramic X-ray detector and the imaged object; c is the X-ray imaging of the PZT ceramic X-ray detector "L" shaped object under the conditions of 125 DEG C, 70 keV X-ray and 0 V applied voltage; d is the X-ray imaging contrast diagram of the PZT ceramic X-ray detector "L" shaped object under the conditions of room temperature 25 DEG C, 70 keV X-ray and 0 V applied voltage. DETAILED DESCRIPTION

[0018] It should be noted that the following detailed description is exemplary in nature and is intended to provide further description of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0019] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0020] In view of the fact that the ceramic is not directly used in the X-ray detector of the semiconductor detector structure in the prior art, it is difficult to exert the advantages of the ceramic material, and the present application proposes an application of the ferroelectric ceramic material in the self-driven X-ray detection.

[0021] In a typical embodiment of the present application, an application of a ferroelectric ceramic material in the preparation of a self-driven X-ray detector or self-driven X-ray detection is provided, wherein the X-ray detector of the self-driven X-ray detector or self-driven X-ray detection is of a semiconductor detector structure, the detection medium in the semiconductor detector structure is the ferroelectric ceramic material, the ferroelectric ceramic material is Pb(Zr x Ti 1-xO3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 12 O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 12 O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O x O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 1-x O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 1 / 3 O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 2 / 3 O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 1-x O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O x O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O

[0022] In some embodiments, the ferroelectric ceramic material is Pb(Zr x Ti 1-x )O3.

[0023] In some embodiments, the ferroelectric ceramic material is Pb(Zr 0.52 Ti 0.48 )O3, abbreviated as PZT. Studies have shown that using PZT as the detection medium of the X-ray detector has the characteristics of high resistivity, low X-ray absorption coefficient, high product of mobility and lifetime, and low dark current drift. The X-ray detector prepared by the semiconductor detector structure of the ceramic material has the advantages of high sensitivity, low detection limit, and high stability. TG-DSC test results show that PZT has no obvious weight loss before 1100°C. This indicates that PZT has high thermal stability. The DSC curve has no obvious sharp peak, indicating that the sample has good crystallinity and no obvious phase change and impurity reaction.

[0024] Another embodiment of the present application provides a high-temperature self-driven X-ray detector, which has a semiconductor detector structure and includes a detection medium layer, two opposite sides of the detection medium layer are respectively provided with a positive electrode layer and a negative electrode layer; the material of the detection medium layer is the ferroelectric ceramic material, and the ferroelectric ceramic material is Pb(Zr x Ti 1-x )O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 12 )O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 12 )O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O x )O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 1-x )O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 1 / 3 )O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 2 / 3 )O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 1-x )O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O x )O3, Pb(Zr, Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O

[0025] In some embodiments, the ferroelectric ceramic material is Pb(Zr x Ti 1-x )O3.

[0026] In some embodiments, the ferroelectric ceramic material is Pb(Zr 0.52 Ti 0.48 )O3.

[0027] Specifically, the preparation process of Pb(Zr 0.52 Ti 0.48 )O3is as follows: mixing raw materials according to stoichiometric ratio, pre-sintering, grinding and tabletting, then re-sintering, annealing and polarization treatment in sequence.

[0028] More specifically, the raw materials are as follows in terms of mole fraction: PbO 100-110 parts, ZrO252-60 parts, TiO240-48 parts. Further, PbO 110-112 parts, ZrO252-53 parts, TiO247-48 parts.

[0029] More specifically, the pre-sintering temperature is 800-850 ℃. Under this condition, the perovskite phase can be initially formed. More specifically, the pre-sintering time is 2-3 h.

[0030] More specifically, the re-sintering temperature is 1200-1250 ℃, and the time is 6-7 h. Under this condition, the sintering is ensured to be sufficient and uniform, thereby ensuring the performance of the ceramic material.

[0031] More specifically, the annealing temperature is 150-200 ℃, and the time is 2-4 h. More specifically, the annealing heating rate is 5-15 ℃ / h. More specifically, the annealing cooling rate is 5-15 ℃ / h.

[0032] More specifically, the polarization treatment temperature is 100-200 ℃, and the voltage is 1500-1700 V. More specifically, the polarization treatment time is 15-25 min. During the polarization treatment, the annealed sheet material is provided with electrodes, then heated and subjected to a direct current electric field for polarization treatment. The electrodes are provided by vacuum plating. After the polarization treatment, the electrodes are removed by mechanical processing such as polishing.

[0033] Pb(Zr 0.52 Ti 0.48 )O3. The raw materials PbO:TiO2:ZrO2 are weighed according to the molar ratio of 1.1:0.48:0.52. Then, the raw materials are put into a agate mortar and ground with an agate pestle. First, the mixture is put into a programmable muffle furnace and sintered at 850°C for 2 hours. After that, it is thoroughly ground and pressed into a sheet shape using a tablet press at 120 MPa. Then the sheet-shaped pellets are put back into the programmable muffle furnace and high-temperature calcination is carried out at 1200°C for 6 hours in a sealed alumina crucible. The specific annealing process of the PZT ceramic is: first, heat the PZT ceramic to 150°C at a rate of 10°C / h, then anneal at 150°C for 2 hours, and finally cool to room temperature at a rate of 10°C / h. The last step is the polarization process: first, vacuum coating forms the upper and lower electrodes. A 1600 V direct current high voltage electric field is applied in a silicon oil bath at 150°C for 20 minutes. Then the sample is slowly cooled to room temperature while the electric field is maintained, and then the electric field is removed to complete the polarization, obtaining a PZT ceramic with excellent X-ray detection performance.

[0034] In some embodiments, the positive electrode layer is made by sputtering.

[0035] In some embodiments, the negative electrode layer is made by sputtering.

[0036] In some embodiments, the thickness of the positive electrode layer is 80-120 nm, preferably 98-102 nm.

[0037] In some embodiments, the thickness of the negative electrode layer is 80-120 nm, preferably 98-102 nm.

[0038] In some embodiments, the thickness of the detection medium layer is 1-2 mm, preferably 1.0-1.5 mm.

[0039] In some embodiments, the material of the positive electrode layer is gold (Au).

[0040] In some embodiments, the material of the negative electrode layer is gold (Au).

[0041] Research shows that when the electrode material is Au, the performance of the lead zirconate titanate-based ceramic material provided by the application can be better exerted.

[0042] Specifically, the preparation steps are as follows: The gold is sputtered on the top surface of the lead zirconate titanate-based ceramic as the positive electrode layer by using an ion sputtering instrument, and the gold is sputtered on the bottom surface of the lead zirconate titanate-based ceramic as the negative electrode layer by using an ion sputtering instrument, to obtain an X-ray detector based on the lead zirconate titanate-based ceramic.

[0043] The third embodiment of the application provides an X-ray detection imaging system, comprising: an X-ray source for emitting X-rays towards an object to be measured; an X-ray detector for receiving X-rays from the X-ray source or passing through the object to be measured and converting the X-rays into electrical signals; the X-ray detector is the high-temperature self-driven X-ray detector according to the second aspect of the present application; an imaging device for converting the electrical signals from the X-ray detector into image information.

[0044] The X-rays emitted by the X-ray source are directed towards the X-ray detector, and the object to be measured is arranged on the path of the X-rays from the X-ray source to the X-ray detector.

[0045] The imaging device can be a computer.

[0046] In order to enable those skilled in the art to more clearly understand the technical solutions of the present application, the technical solutions of the present application will be described in detail below with specific examples.

[0047] The raw materials used in the examples, unless otherwise specified, are commercially available; the methods used, unless otherwise specified, are prior art.

[0048] Example 1 An X-ray detector based on PZT ceramic includes a gold negative electrode layer, a PZT ceramic, and a gold positive electrode layer arranged in order from bottom to top. The thickness of the negative electrode layer is 100 nm. The thickness of the positive electrode layer is 100 nm. The negative electrode layer and the positive electrode layer are arranged on the lower surface (1.5 mm x 1.5 mm) and the upper surface (1.5 mm x 1.5 mm) of the PZT ceramic, respectively. The PZT ceramic is a cuboid with a length of 12 mm, a width of 14 mm, and a height of 1.5 mm.

[0049] The preparation method of the PZT ceramic includes the following steps: First, raw materials PbO2, ZrO2 and TiO2 are mixed according to the component composition of the molar percentage: the molar ratio of PbO: TiO2: ZrO2 is 1.1:0.48:0.52. Then, the raw materials are put into an agate mortar and ground thoroughly with an agate pestle. First, the mixture is put into a programmable muffle furnace and sintered at 850℃ for 2 hours. After that, it is ground thoroughly and pressed into a sheet shape using a tablet press. Then the sheet-shaped pellets are put back into the programmable muffle furnace and subjected to high-temperature calcination at 1200℃ for 6 hours in a sealed alumina crucible. The specific annealing process of the PZT ceramic is: first, heat the PZT ceramic to 150℃ at a rate of 10℃ / h, then anneal at 150℃ for 2 hours, and finally cool to room temperature at a rate of 10℃ / h. The next step is the polarization process: first, vacuum coating forms the upper and lower electrodes. Apply a 1600 V direct current high voltage electric field in a silicon oil bath at 150℃ for 20 minutes. Then slowly cool the sample to room temperature while maintaining the electric field, and then remove the electric field to complete the polarization, obtaining a PZT ceramic with excellent X-ray detection performance. Finally, the ceramic sheet-shaped photo with a length of 12 mm, a width of 14 mm, and a height of 1.5 mm is polished out as shown in Figure 1 .

[0050] The preparation method of the above-mentioned PZT ceramic-based X-ray detector comprises the following steps: sputtering gold as the positive electrode layer on the top surface of the PZT ceramic using an ion sputtering instrument, and sputtering gold as the negative electrode layer on the bottom surface of the PZT ceramic using an ion sputtering instrument, to obtain a PZT ceramic-based X-ray detector. The structural diagram is shown in Figure 2 .

[0051] The prepared PZT ceramic and α- Se 、β- Ga2O3 、 Cd 0.9 Zn 0.1 Te. Figure 3 The X-ray absorption coefficients of Te and MAPbBr3 are theoretically calculated using a photon cross-section database. The X-ray absorption coefficient is related to the elements contained in the compound, and is independent of the preparation method and structure. The theoretical calculation results are shown in Figure 3 . It can be seen from α- Se 、β- Ga2O3 0.9 Zn 0.1 Te that the X-ray absorption coefficient of the PZT ceramic is significantly higher than

[0052] The resistance of the prepared PZT ceramic is obtained by testing the I-V curve, and the test results are shown in Figure 4 . It can be seen from Figure 4 that the resistivity of the PZT ceramic is 3.84 × 1012 Ω cm.

[0053] The carrier mobility-lifetime product of the prepared PZT ceramic was obtained by measuring photocurrent data, and the test results are as follows: Figure 5 As shown, by Figure 5 It can be seen that the carrier mobility-lifetime product of TeO2-Ga2O3 ceramic is 1.15 × 10⁻⁶. -3 cm 2 V -1 .

[0054] The photocurrent of the fabricated PZT ceramic X-ray detector was tested under different doses. The X-ray dose was increased by continuously increasing the applied X-ray tube current at an X-ray energy of 40 keV. The test results are as follows: Figure 6 As shown in a, by Figure 6 As can be seen from a, by increasing the X-ray dose rate, the photocurrent of the X-ray detector continuously increases.

[0055] The sensitivity of the fabricated PZT ceramic X-ray detector at X-ray energies was tested by... Figure 6 The data was obtained by fitting the current density and dose rate, and the fitting results are as follows: Figure 7 As shown, at room temperature (25°C), 40 keV X-rays, and a voltage of 700 V, the sensitivity of the PZT ceramic X-ray detector is 805.91 μC Gy. air -1 cm -2 .

[0056] The photocurrent of the fabricated PZT ceramic self-driven X-ray detector was tested at different temperatures with an X-ray energy of 40 keV and an applied voltage of 0V. The X-ray dose was increased by continuously increasing the applied X-ray tube current. The test results are as follows: Figure 8 As shown, by Figure 8 It can be seen that by increasing the X-ray dose rate, the photocurrent of the X-ray detector continuously increases.

[0057] The self-driving sensitivity of the fabricated PZT ceramic high-temperature self-driven X-ray detector under no external voltage was tested. Figure 8 The data was obtained by fitting the current density and dose rate, and the fitting results are as follows: Figure 9 As shown, at 125℃, 40 keV X-rays, and 0V applied voltage, the sensitivity of the PZT ceramic self-driven X-ray detector is 544.69 μC Gy. air -1 cm -2 .

[0058] The detection line of the fabricated PZT ceramic X-ray detector was tested at a dose rate with a signal-to-noise ratio of 3. The test results are as follows:Figure 10 As shown in FIG. 8, the minimum detectable limit of the PZT ceramic X-ray detector is 7.31 nGy at 40 keV X-ray and 1000 V voltage air s -1 .

[0059] The dark current drift curve of the prepared PZT ceramic X-ray detector was tested, and the dark current size of the X-ray detector within 1000 s was tested to finally calculate. The test results are shown in FIG. 9. Figure 11 As shown in FIG. 9, the dark current drift of the PZT ceramic X-ray detector is 7.63 x 10 -10 nA cm -1 s -1 V -1 .

[0060] The X-ray radiation dose was calibrated using an X-ray detector, and different doses of X-rays could be generated by adjusting the tube voltage and tube current of the high-voltage generator. The relationship between the photocurrent and the X-ray dose rate of the high-voltage generator is shown in Table 1. The data in Table 1 show that as the photocurrent of the high-voltage generator increases, the generated X-ray dose rate also increases.

[0061] Table 1. Relationship between photocurrent and dose rate at 40 keV X-ray energy

[0062] Example 2 A PZT ceramic-based X-ray detector includes a gold negative electrode layer, a PZT ceramic, and a gold positive electrode layer arranged in order from bottom to top. The thickness of the negative electrode layer is 100 nm. The thickness of the positive electrode layer is 100 nm. The negative electrode layer and the positive electrode layer are arranged on the lower surface (1.5 mm x 1.5 mm) and the upper surface (1.5 mm x 1.5 mm) of the PZT ceramic, respectively. The PZT ceramic is a cuboid with a length of 12 mm, a width of 14 mm, and a height of 1.5 mm.

[0063] The preparation method of the PZT ceramic is the same as that of Example 1.

[0064] The photocurrent of the prepared PZT ceramic X-ray detector under different doses was tested, and the X-ray energy was 70 keV, and the X-ray dose was increased by continuously increasing the X-ray tube current, and the test results are shown in FIG. 10b. Figure 6 b Figure 6 b, the photocurrent of the X-ray detector continuously increases by increasing the X-ray dose rate.

[0065] The sensitivity of the prepared PZT ceramic X-ray detector under X-ray energy was tested, and the current density and dose rate were fitted by Figure 6 data fitting, and the fitting results are shown in FIG. 11b.Figure 7 As shown, at room temperature (25°C), 70 keV X-rays, and a voltage of 700 V, the sensitivity of the PZT ceramic X-ray detector is 1196.82 μC Gy. air -1 cm -2 .

[0066] The photocurrent of the fabricated PZT ceramic self-driven X-ray detector was tested at different temperatures with an X-ray energy of 70 keV and an applied voltage of 0V. The X-ray dose was increased by continuously increasing the applied X-ray tube current. The test results are as follows: Figure 8 As shown, by Figure 8 It can be seen that by increasing the X-ray dose rate, the photocurrent of the X-ray detector continuously increases.

[0067] The self-driving sensitivity of the prepared PZT ceramic high-temperature self-driven X-ray detector was tested under no external voltage. Figure 8 The data was obtained by fitting the current density and dose rate, and the fitting results are as follows: Figure 9 As shown, at 125℃, 70 keV X-rays, and 0 V applied voltage, the sensitivity of the PZT ceramic self-driven X-ray detector is 544.69 μC Gy. air -1 cm -2 .

[0068] The detection line of the fabricated PZT ceramic X-ray detector was tested at a dose rate with a signal-to-noise ratio of 3. The test results are as follows: Figure 10 As shown in figure a, the lowest detection limit of the PZT ceramic X-ray detector is 31.34 nGy under 70 keV X-rays and 1000 V voltage. air s -1 .like Figure 10 As shown in b, at 125℃, 70 keV X-rays, and 0 V voltage, the lowest detection limit of the PZT ceramic X-ray detector is 10.71 nGy. air s -1 .

[0069] The dark current drift curve of the fabricated PZT ceramic X-ray detector was obtained by measuring the dark current of the X-ray detector over 1000 s and then calculating the result. The test results are as follows: Figure 11 As shown, the dark current drift of the PZT ceramic X-ray detector is 7.63 × 10⁻⁶. -10 nA cm -1 s -1 V -1 .

[0070] The X-ray radiation dose was calibrated using an X-ray detector. Different doses of X-rays can be generated by adjusting the tube voltage and tube current of the high-voltage generator. The relationship between the photocurrent and the X-ray dose rate of the high-voltage generator at a tube voltage of 70 keV is shown in Table 2. The data in Table 2 show that as the photocurrent of the high-voltage generator increases, the generated X-ray dose rate also increases.

[0071] Table 2. Relationship between photocurrent and dose rate at 70 keV X-ray energy

[0072] The above preparation method of the self-driven X-ray detection imaging based on PZT ceramic includes the following steps: First, a 12x14 array of PZT ceramic was created, i.e., a 14x12 mask plate was used, gold was sputtered on the top surface of the PZT ceramic as the positive electrode layer using an ion sputtering instrument, and gold was sputtered on the bottom surface of the PZT ceramic as the negative electrode layer using an ion sputtering instrument to evaluate its X-ray imaging capability. Figure 12 b), the upper and lower positive and negative electrodes were connected using a metal probe, and a tungsten anode X-ray tube was selected as the X-ray source, and the X-ray energy could be adjusted in the range of 40-150 keV. On the basis of calibrating the radiation dose rate, different X-ray dose rates can be obtained by changing the tube voltage and current.

[0073] The self-made PZT ceramic high-temperature array self-driven X-ray detection imaging was tested, and the schematic diagram of the array self-driven X-ray detector and its imaging system is shown in Figure 12 a. The object used for photography is an "L" shaped piece with a size of 4 mm x 4 mm. Then the object was placed on the self-made platform as shown in Figure 12 b. Figure 12 c is the imaging diagram under X-ray irradiation at 125℃, photoelectron energy of 70 keV, and applied voltage of 0 V. Obviously, the array self-driven X-ray detector finally produces a clear image shape, and the "L" shaped pattern is not distorted.

[0074] The self-made PZT ceramic high-temperature array self-driven X-ray detection imaging was tested, and the schematic diagram of the array self-driven X-ray detector and its imaging system is shown in Figure 12 a. The object used for photography is an "L" shaped piece with a size of 4 mm x 4 mm. Then the object was placed on the self-made platform as shown in Figure 12 b. Figure 12d is the imaging figure under X-ray irradiation at room temperature 25℃, photoelectron energy 70 keV and applied voltage 0 V. Apparently, the shape edge of the image finally produced by the array self-driven X-ray detector is somewhat unclear, which further indicates the importance of high sensitivity to X-ray imaging. In self-driven X-ray detection imaging, due to its low ion migration, excellent sensitivity at high temperature and extremely low detection limit, the PZT ceramic self-driven X-ray detector is expected to be applied in 70 keV X-ray detection, especially in high temperature environment.

[0075] Example 3 A PZT ceramic-based X-ray detector includes a gold negative electrode layer, a PZT ceramic and a gold positive electrode layer arranged in sequence from bottom to top. The thickness of the negative electrode layer is 100 nm. The thickness of the positive electrode layer is 100 nm. The negative electrode layer and the positive electrode layer are arranged on the lower surface (1.5 mm x 1.5 mm) and the upper surface (1.5 mm x 1.5 mm) of the PZT ceramic respectively. The PZT ceramic is a cuboid with a length of 12 mm, a width of 14 mm and a height of 1.5 mm.

[0076] The preparation method of the PZT ceramic is the same as that in Example 1.

[0077] The photoelectric current of the prepared PZT ceramic X-ray detector under different doses was tested, which was obtained by continuously increasing the X-ray tube current to increase the X-ray dose at an X-ray energy of 120 keV, and the test results are shown in Figure 6 c, it can be seen that the photoelectric current of the X-ray detector increases continuously by increasing the X-ray dose rate. Figure 6 c.

[0078] The sensitivity of the prepared PZT ceramic X-ray detector under X-ray energy was tested, which was obtained by Figure 6 Data fitting of current density and dose rate, and the fitting results are shown in Figure 7 , the sensitivity of the PZT ceramic X-ray detector is 901.26 μC Gy air -1 cm -2 .

[0079] The photoelectric current of the prepared PZT ceramic self-driven X-ray detector under different temperatures was tested under an applied voltage of 0 V and an X-ray energy of 120 keV, which was obtained by continuously increasing the X-ray tube current to increase the X-ray dose, and the test results are shown in Figure 8 c, it can be seen that the photoelectric current of the X-ray detector increases continuously by increasing the X-ray dose rate. Figure 8

[0080] ​The self-driven sensitivity of the prepared PZT ceramic high-temperature self-driven X-ray detector under no external voltage was tested, and the self-driven sensitivity was obtained by Figure 8 Data fitting current density and dose rate, and the fitting results are shown in Figure 9 Fig. 3, at 75℃, 120 keV x-rays and 0 V external voltage, the sensitivity of the PZT ceramic self-driven X-ray detector is 379.01 μC Gy air -1 cm -2 .

[0081] The detection line of the prepared PZT ceramic X-ray detector was tested, which was the dose rate when the signal-to-noise ratio was 3. The test results are shown in Figure 10 Fig. 4, at 120 keV X-rays and 1000 V voltage, the minimum detection limit of the PZT ceramic X-ray detector is 20.16 nGy air s -1 .

[0082] The dark current drift curve of the prepared PZT ceramic X-ray detector was tested, and the dark current size of the X-ray detector within 1000 s was tested, and finally calculated. The test results are shown in Figure 11 Fig. 5, the dark current drift of the PZT ceramic X-ray detector is 7.63 x 10 -10 nA cm -1 s -1 V -1 .

[0083] The X-ray radiation dose was calibrated by using an X-ray detector, and different doses of X-rays could be generated by adjusting the tube voltage and tube current of the high-voltage generator. The relationship between the photocurrent and the X-ray dose rate of the high-voltage generator when the tube voltage is 120 keV is shown in Table 3. The data in Table 3 shows that as the photocurrent of the high-voltage generator increases, the generated X-ray dose rate also increases.

[0084] Table 3. Relationship between photocurrent and dose rate under 120 keV X-ray energy

[0085] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. The application of a ferroelectric ceramic material in the fabrication of a self-driven X-ray detector or a self-driven X-ray probe, wherein the self-driven X-ray detector or the self-driven X-ray probe employs a semiconductor detector structure, and the detection medium in the semiconductor detector structure is the ferroelectric ceramic material, wherein the ferroelectric ceramic material is Pb(Zr) x Ti 1-x )O3, Pb(Zr,Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 12 Bi4Ge3O 12 、Sr x Ba 1-x Nb₂O₆, Pb(Mg) 1 / 3 Nb 2 / 3 ) 1-x Ti x One or more of O3, 0≤x≤1.

2. The application as described in claim 1, characterized in that, The ferroelectric ceramic material is Pb(Zr) x Ti 1-x )O3.

3. The application as described in claim 1, characterized in that, The ferroelectric ceramic material is Pb(Zr) 0.52 Ti 0.48 )O3.

4. A high-temperature self-driven X-ray detector, characterized in that, Its structure is a semiconductor detector structure, including a detection dielectric layer, with a positive electrode layer and a negative electrode layer respectively disposed on two opposite sides of the detection dielectric layer; the material of the detection dielectric layer is the ferroelectric ceramic material, which is Pb(Zr) x Ti 1-x )O3, Pb(Zr,Ti)O3: Mn, BaTiO3, BiGaO3, Bi4Ti3O 12 Bi4Ge3O 12 、Sr x Ba 1-x Nb₂O₆, Pb(Mg) 1 / 3 Nb 2 / 3 ) 1-x Ti x One or more of O3, 0≤x≤1.

5. The high-temperature self-driven X-ray detector as described in claim 4, characterized in that, The ferroelectric ceramic material is Pb(Zr) x Ti 1-x O3; Alternatively, the ferroelectric ceramic material is Pb(Zr) 0.52 Ti 0.48 )O3.

6. The high-temperature self-driven X-ray detector as described in claim 5, characterized in that, Pb(Zr 0.52 Ti 0.48 The preparation process of O3 is as follows: after mixing the raw materials according to the stoichiometric ratio, they are pre-sintered, then ground and pressed into tablets, and then re-sintered, annealed and polarized in sequence.

7. The high-temperature self-driven X-ray detector as described in claim 6, characterized in that, Based on molar parts, it is made from the following raw materials: PbO 100~110 parts, ZrO2 52~60 parts, TiO2 40~48 parts; Alternatively, the pre-sintering temperature is 800~850℃; Alternatively, the resintering temperature is 1200~1250 ℃, and the time is 6~7 h; Alternatively, the annealing temperature is 150~200℃, and the time is 2~4 hours; Alternatively, the polarization treatment temperature is 100~200 ℃ and the voltage is 1500~1700 V.

8. The high-temperature self-driven X-ray detector as described in claim 4, characterized in that, The positive electrode layer is fabricated using a sputtering method; Alternatively, the negative electrode layer can be fabricated using a sputtering method.

9. The high-temperature self-driven X-ray detector as described in claim 4, characterized in that... The thickness of the positive electrode layer is 98~102 nm; Alternatively, the thickness of the negative electrode layer is 98~102nm; Alternatively, the thickness of the detection medium layer is 1.0~1.5mm; Alternatively, the positive electrode layer may be made of gold; Alternatively, the negative electrode layer may be made of gold.

10. An X-ray detection and imaging system, characterized in that, include: An X-ray source is used to emit X-rays onto an object being tested. An X-ray detector is used to receive X-rays from an X-ray source or passing through the object being measured, and to convert the X-rays into electrical signals. The X-ray detector is the high-temperature self-driven X-ray detector according to any one of claims 4 to 9; An imaging device used to convert electrical signals from an X-ray detector into image information.

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