Silicon carbide-based ultrathin flexible neutron detector and preparation method and application thereof
By combining silicon carbide thinning technology with flexible substrates, and designing flexible conductive traces and neutron conversion layers, the stability problem of traditional silicon carbide detectors in flexible and high-temperature, high-radiation environments has been solved, achieving stable radiation detection in extreme environments, suitable for complex spaces and wearable applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HEFEI INSTITUTE OF PHYSICAL SCIENCE CHINESE ACADEMY OF SCIENCES
- Filing Date
- 2026-05-06
- Publication Date
- 2026-06-26
AI Technical Summary
Existing radiation detector materials have limitations in flexible, bending, and integrated applications. Traditional silicon carbide detectors are not stable enough in high-temperature and high-radiation environments and cannot meet the requirements of complex space environments.
By combining silicon carbide thinning technology with a flexible substrate, an ultrathin flexible detector is formed. Through the design of flexible conductive traces and a neutron conversion layer, the detector can be bent and deformed, and maintain stability in extreme environments.
It achieves stable radiation detection performance in extreme environments, adapts to complex space environments, is suitable for wearable and wearable applications, reduces mechanical stress and noise, and improves the long-term operational reliability of the device.
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Figure CN122294604A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of radiation detectors, and more particularly to an ultrathin flexible neutron detector based on silicon carbide, its fabrication method, and its applications. Background Technology
[0002] With the continuous advancement of science and technology, radiation detectors are increasingly widely used in various fields, especially in high-risk industries such as nuclear energy, aerospace, medicine, and national defense. Traditional radiation detectors mostly use materials such as silicon and scintillation crystals. While these materials have certain advantages in radiation detection, they still have limitations in terms of sensitivity, adaptability to operating environments, and structural flexibility. Currently, although many radiation detector materials can achieve high detection efficiency, these materials are usually relatively fragile and susceptible to external physical stress, leading to performance degradation. Especially in applications requiring flexibility, bending, or integration, these traditional detectors often cannot meet design requirements. To address these issues, researchers have conducted extensive research on the development of novel radiation detector materials.
[0003] Silicon carbide (SiC), as a semiconductor material with excellent physical properties, has attracted increasing attention in the field of radiation detectors in recent years. Silicon carbide possesses high thermal conductivity, strong radiation resistance, good electrical properties and mechanical strength, and remains stable even under high temperature and high radiation environments, making it ideal for radiation detection applications. However, most existing silicon carbide radiation detectors utilize rigid materials and traditional manufacturing methods, which limits their applications in areas such as flexibility, high integration, and thinness. To overcome these shortcomings, more and more researchers are focusing on the possibility of combining flexible materials with silicon carbide thinning techniques, hoping to achieve a silicon carbide radiation detector that can maintain detection performance while also possessing flexibility and bendability. Summary of the Invention
[0004] To overcome the shortcomings of existing radiation detectors in terms of structural flexibility, adaptability, and performance stability, this invention provides an ultrathin flexible neutron detector based on silicon carbide, its fabrication method, and its applications. This invention combines silicon carbide thinning technology with a flexible substrate to create an ultrathin flexible detector that possesses both excellent radiation detection performance and the ability to adapt to bending deformation, thus showing broad application prospects.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] An ultrathin flexible neutron detector based on silicon carbide, comprising:
[0007] A flexible substrate, and multiple ultrathin silicon carbide radiation detector units disposed on the flexible substrate, wherein the multiple ultrathin silicon carbide radiation detector units are spaced apart from each other to form a non-continuous distributed arrangement;
[0008] A flexible circuit, which is electrically connected to each ultrathin silicon carbide radiation detector unit, includes flexible conductive traces for connecting the ultrathin silicon carbide radiation detector units in series or in parallel.
[0009] A neutron conversion layer is used to convert neutrons into detectable charged particle signals; the neutron conversion layer is disposed on the surface of an ultrathin silicon carbide radiation detector unit, or the neutron conversion layer is sandwiched between two ultrathin silicon carbide radiation detector units;
[0010] A flexible encapsulation protective layer covers the surface of the silicon carbide-based ultrathin flexible neutron detector.
[0011] Among them, the flexible conductive trace adopts an extendable trace pattern; the trace pattern of the flexible conductive trace is any one or a combination of meandering, serpentine, wavy, zigzag or fractal structure.
[0012] The flexible substrate is polyimide, polyethylene terephthalate, polybutylene terephthalate, or a composite flexible polymer material.
[0013] The neutron conversion layer includes... 10 Material B, containing 6 Li materials or rich in 1 At least one or more mixed material layers in material H, wherein... 10 Material B includes B, B4C, B2O3, and BN; containing 6 Li materials include Li, LiF, LiH, and Li₂O; rich in... 1 H materials include polyethylene, polypropylene, polymethyl methacrylate, paraffin wax, silicone sealant, and hydrogenated polymers;
[0014] The ultrathin silicon carbide radiation detector unit is a Schottky structure, PN structure, PIN structure, heterojunction structure, or MSM structure.
[0015] The discontinuous distributed arrangement can be an array-type arrangement, a grid-type arrangement, or an island-bridge structure arrangement.
[0016] The ultrathin silicon carbide radiation detector unit is integrated onto a flexible substrate by transfer printing or epitaxial lift-off.
[0017] The neutron conversion layer is deposited on the surface of the ultrathin silicon carbide radiation detector unit by thermal evaporation, sputtering deposition, chemical deposition or spin coating deposition; or the neutron conversion layer is made into a flexible thin layer and covered on the surface of the ultrathin silicon carbide radiation detector unit, or the neutron conversion layer is sandwiched between two ultrathin silicon carbide radiation detector units to form a layered sandwich structure.
[0018] The thickness of the ultrathin silicon carbide radiation detector unit is 10μm to 100μm; the thickness of the neutron conversion layer is 0.1μm to 100μm; and the thickness of the flexible encapsulation protective layer is 6μm to 10μm.
[0019] The flexible circuit is also connected to a signal processing module, which is used to amplify, filter, and acquire data of the radiated signal.
[0020] The above-mentioned method for fabricating an ultrathin flexible neutron detector based on silicon carbide includes the following steps:
[0021] S1: Clean the surface of the flexible substrate;
[0022] S2: Multiple ultrathin silicon carbide radiation detector units are integrated on a flexible substrate. The multiple ultrathin silicon carbide radiation detector units are arranged in a non-continuous distributed manner with a preset spacing. The ultrathin silicon carbide radiation detector units are connected by flexible conductive traces.
[0023] S3: Prepare a neutron conversion layer; the neutron conversion layer is deposited on the surface of an ultrathin silicon carbide radiation detector unit by thermal evaporation, sputtering deposition, chemical deposition or spin coating deposition; or the neutron conversion layer is made into a flexible thin layer and covered on the surface of the ultrathin silicon carbide radiation detector unit;
[0024] S4: Fabricate a flexible encapsulation protective layer covering the entire surface of the silicon carbide-based ultrathin flexible neutron detector.
[0025] The preparation method also includes the following steps:
[0026] S5: Fold the entire silicon carbide-based ultrathin flexible neutron detector in a Swiss roll or ingot-like manner.
[0027] The above-mentioned application of silicon carbide-based ultrathin flexible neutron detectors in neutron radiation detection.
[0028] The beneficial effects of this invention are as follows:
[0029] (1) The ultrathin flexible neutron detector based on silicon carbide of the present invention obtains an ultrathin silicon carbide film through femtosecond laser ablation, photoelectrochemical etching, or substrate thinning, and integrates it with a flexible polyimide substrate. Combined with a serpentine stretchable circuit design, the device can withstand bending, winding, and folding (such as Swiss roll, stacked ingot, and other complex structures). It achieves a significant expansion of the detection area within a limited volume, making it suitable for complex space environments and novel application scenarios such as wearable and adhesive types.
[0030] (2) The silicon carbide material used in this invention has excellent high temperature resistance, radiation resistance and chemical stability, enabling the invention to work stably in extreme environments such as high temperature and high radiation. At the same time, through flexible encapsulation protective layer and optimized electrode and interconnect structure design, leakage current and noise are effectively reduced, improving the long-term reliability and stability of the device, and meeting the application needs of nuclear industry, aerospace and radiation monitoring fields.
[0031] (3) The silicon carbide-based ultrathin flexible neutron detector of the present invention can not only adapt to bending deformation, but also work efficiently in extreme environments, making it suitable for a wider range of applications. Attached Figure Description
[0032] Figure 1 This is a schematic diagram of the structure of the silicon carbide-based ultrathin flexible neutron detector of the present invention.
[0033] Figures 2 to 4 This is a schematic diagram of the Swiss roll-up process of an ultrathin flexible neutron detector based on silicon carbide according to Embodiment 2 of the present invention.
[0034] Figure 5 This is a schematic diagram of the "ingot-shaped" convolution structure of an ultrathin flexible neutron detector based on silicon carbide according to Embodiment 3 of the present invention.
[0035] Figure 6 This is a side view of the "ingot-shaped" convolution structure of the silicon carbide-based ultrathin flexible neutron detector according to Embodiment 3 of the present invention.
[0036] The attached figures are labeled as follows: 1-flexible substrate, 2-ultra-thin silicon carbide radiation detector unit, 3-flexible circuit, 4-neutron conversion layer. Detailed Implementation
[0037] The technical solutions of the embodiments of the invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the invention, and not all of them. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. Based on the embodiments of the invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the invention.
[0038] It should be noted that if the embodiments of the invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.
[0039] Furthermore, if the embodiments of the invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, "multiple" refers to two or more. Moreover, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of a person skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the invention.
[0040] See Figure 1 The present invention provides an ultrathin flexible neutron detector based on silicon carbide, which includes a flexible substrate 1, an ultrathin silicon carbide radiation detector unit 2, a flexible circuit 3, a neutron conversion layer 4, and a flexible encapsulation protective layer.
[0041] Multiple ultrathin silicon carbide radiation detector units 2 are disposed on the flexible substrate 1, and the multiple ultrathin silicon carbide radiation detector units 2 are spaced apart from each other to form a non-continuous distributed arrangement; preferably, the ultrathin silicon carbide radiation detector units 2 maintain a spacing of 2-7 mm between them.
[0042] The flexible circuit 3 is electrically connected to each ultrathin silicon carbide radiation detector unit 2. The flexible circuit 3 includes flexible conductive lines for connecting each ultrathin silicon carbide radiation detector unit in series or in parallel.
[0043] The neutron conversion layer 4 is used to convert neutrons into detectable charged particle signals; the neutron conversion layer 4 is disposed on the surface of the ultrathin silicon carbide radiation detector unit 2, or the neutron conversion layer 4 is sandwiched between two ultrathin silicon carbide radiation detector units 2.
[0044] The flexible encapsulation protective layer covers the surface of the silicon carbide-based ultrathin flexible neutron detector.
[0045] Preferably, the flexible conductive traces adopt a stretchable trace pattern so that when the silicon carbide-based ultrathin flexible neutron detector is bent, the bending stress is mainly released by the flexible substrate and stretchable wires, thereby reducing the mechanical stress acting on the device unit and maintaining electrical connection stability.
[0046] Even better, the routing pattern of the flexible conductive trace is any one or a combination of meandering, serpentine, wavy, zigzag or fractal structures.
[0047] The flexible substrate 1 is made of polyimide, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), or a composite flexible polymer material.
[0048] The neutron conversion layer 4 includes... 10 Material B, containing 6 Li materials or rich in 1 At least one or more mixed material layers in material H, wherein... 10 Material B includes 10 B. 10 B4C 10 B2O3 and 10 BN; containing 6 Li materials include 6 Li, 6 LiF, 6 LiH and 6 Li2O; rich in Li2O; 1 H materials include polyethylene, polypropylene, polymethyl methacrylate, paraffin wax, silicone sealant, and hydrogenated polymers;
[0049] The ultrathin silicon carbide radiation detector unit 2 is a Schottky structure, PN structure, PIN structure, heterojunction structure or MSM (metal-semiconductor-metal) structure.
[0050] Preferably, the discontinuous distributed arrangement is an array arrangement, a grid arrangement, or an island-bridge structure arrangement.
[0051] The ultrathin silicon carbide radiation detector unit 2 is integrated onto the flexible substrate 1 by transfer printing or epitaxial lift-off.
[0052] The neutron conversion layer 4 is deposited on the surface of the ultrathin silicon carbide radiation detector unit 2 by thermal evaporation, sputtering deposition, chemical deposition or spin coating deposition; or the neutron conversion layer 4 is made into a flexible thin layer and covered on the surface of the ultrathin silicon carbide radiation detector unit 2, or the neutron conversion layer 4 is sandwiched between two ultrathin silicon carbide radiation detector units 2 to form a layered sandwich structure.
[0053] Preferably, the thickness of the ultrathin silicon carbide radiation detector unit 2 is 10μm to 100μm; the thickness of the neutron conversion layer 4 is 0.1μm to 100μm; and the thickness of the flexible encapsulation protective layer is 6μm to 10μm.
[0054] The flexible circuit 3 is also connected to a signal processing module, which is used to amplify, filter, and acquire data of the radiated signal.
[0055] Example 1:
[0056] Part 1: Fabrication of an ultrathin silicon carbide radiation detector unit with a Schottky structure.
[0057] This embodiment uses an N-type 4H-SiC substrate with a thickness of 350 μm, a diameter of 6 inches, and a resistivity of approximately 0.015 Ω·cm. Epitaxial growth with a thickness of 20 μm and a doping concentration of 1.0 × 10⁻⁶ is performed on this substrate. 14 cm -3 The N-type 4H-SiC semiconductor layer was grown. After growth, a femtosecond laser was focused on the area below 35-38 μm on the surface to complete wafer-level scanning, forming a uniform modified layer below 35-38 μm on the surface. Then, the modified layer was separated from the upper epitaxial structure and the lower substrate by ultrasonication to obtain ultrathin silicon carbide. Based on this, a Schottky structure ultrathin silicon carbide radiation detector unit with a basic unit area of 10 mm × 10 mm was fabricated.
[0058] Part 2: Fabrication of an ultrathin flexible neutron detector based on silicon carbide.
[0059] (1) Polyimide (PI) film was selected as the flexible substrate material because it has good mechanical strength, temperature resistance and flexibility. The thickness of the polyimide film was controlled at 30 μm to provide sufficient support while also having good bending properties. The surface of the film was cleaned to remove possible contaminants and impurities.
[0060] (2) Multiple ultrathin silicon carbide radiation detector units 2 are bonded and integrated onto a flexible substrate 1. The ultrathin silicon carbide radiation detector units 2 are spaced approximately 2 mm apart, forming a discontinuous distributed arrangement. Each ultrathin silicon carbide radiation detector unit 2 is contacted via a metal electrode (such as aluminum) to ensure good electrical performance. A flexible circuit 3 is fabricated on a flexible polyimide substrate using silver nanowire printing technology. The flexible circuit 3 adopts a serpentine structure, which ensures both good conductivity and sufficient ductility when the device is bent. The flexible circuit 3 connects each ultrathin silicon carbide radiation detector unit 2 in series via extendable traces to form a complete circuit network. In the circuit design, metal wires (such as silver or copper) are used for electrical connections to ensure low resistance and high stability of the circuit.
[0061] (3) A 92% abundance layer of silicon carbide was deposited on the surface of the ultrathin silicon carbide radiation detector unit 2 using sputtering technology. 10 B serves as the neutron conversion layer. With a thickness of 3 μm, the neutron conversion layer efficiently converts incident neutrons into charged particle signals, thereby improving the sensitivity of radiation detection. During deposition, it is ensured that the neutron conversion layer uniformly covers the entire surface of the detector unit.
[0062] (4) Cover the entire surface of the detector with a flexible encapsulation protective layer with a thickness of 10 μm.
[0063] The detection signal is read and processed using a standard NIM readout electronics system. The effective detection area of the silicon carbide-based ultrathin flexible neutron detector obtained in this embodiment is 1 mm. 2 -100 cm 2 At a working voltage of -100 V, the device leakage current is less than 10 nA. When the forming time is 1 μs and the energy threshold is set to 300 keV, the thermal neutron detection efficiency is 4%.
[0064] Example 2:
[0065] like Figure 2 As shown, the ultrathin flexible radiation detector based on silicon carbide in this embodiment has a PIN structure and employs... 6 LiF is used as a neutron conversion material, and large-area, high-efficiency integration is achieved through a Swiss roll folding structure.
[0066] Part 1: Fabrication of a PIN structure ultrathin silicon carbide radiation detector unit.
[0067] A p-type 4H-SiC substrate with a thickness of 350 μm, a diameter of 6 inches, and a resistivity of approximately 0.015 Ω·cm was selected. NIP structures were epitaxially grown sequentially on this substrate: first, a structure with a thickness of approximately 0.5 μm and a doping concentration of 1.0 × 10⁻⁶ was grown.18 cm -3 N + A sacrificial layer of type 20 μm thickness with a doping concentration of 5.0 × 10⁻⁶ is grown on it. 13 cm -3 The intrinsic (Type I) epitaxial layer was grown; finally, a thickness of 1 μm and a doping concentration of 5.0 × 10⁻⁶ were grown. 18 cm -3 A P-type epitaxial layer is formed, thus creating a complete PIN structure. This structure facilitates the formation of a wider depletion region, improving the collection efficiency of charged particles. After epitaxial growth, photoelectrochemical etching is used to selectively etch the PIN epitaxial layer structure from the substrate, obtaining an ultrathin silicon carbide detector film with a thickness of approximately 30 μm.
[0068] Further, through photolithography and etching processes, it was divided into PIN-type detector array units with a unit size of 8 mm × 8 mm.
[0069] In terms of electrode design, nickel / gold (Ni / Au) is deposited on the surface of the P-type layer as an ohmic contact electrode, and titanium / aluminum (Ti / Al) is deposited on the N-type side through opening a window to form a back electrode. The ohmic contact is formed by rapid annealing at 850℃ in a nitrogen atmosphere for 3 min.
[0070] Part 2: Fabrication of an ultrathin flexible neutron detector based on silicon carbide.
[0071] (1) Flexible substrate 1 is made of polyimide (PI) film with a thickness of 25 μm to balance mechanical support and flexible bending ability. Plasma cleaning is performed on its surface to improve the interfacial adhesion.
[0072] (2) The prepared PIN structure ultrathin silicon carbide radiation detector units are transferred in an array onto a flexible PI substrate, with a spacing of approximately 5 mm between adjacent units to accommodate the stress distribution of the subsequent winding structure. The flexible circuit is fabricated using a silver nanowire and copper composite conductive material through a combination of inkjet printing and photolithography. The wires are designed as a serpentine, stretchable structure to improve reliability during bending and winding. Each PIN structure ultrathin silicon carbide radiation detector unit can be connected in a hybrid series-parallel configuration to optimize signal output and impedance matching.
[0073] (3) A neutron conversion layer was deposited on the incident surface of the PIN-structured ultrathin silicon carbide radiation detector unit, and a lithium fluoride (LiF) thin film was deposited as the neutron conversion material using a thermal evaporation method. The thickness of the LiF layer was controlled at 5 μm, of which... 6 The Li isotope enrichment is preferably above 90% to improve thermal neutron capture efficiency. This conversion layer can... 6 Li(n, α) 3The H reaction produces high-energy charged particles, thereby generating a detectable signal in the SiC depletion region.
[0074] (4) A modified PI material flexible encapsulation protective layer with a thickness of about 8 μm is further deposited on the conversion layer to enhance the environmental stability and mechanical reliability of the device without significantly reducing the neutron transmittance.
[0075] (5) After the device fabrication is completed, see Figures 2 to 4 The entire ultrathin flexible neutron detector is wound in a Swiss-roll multi-layer manner along one axis, which enables the ultrathin flexible neutron detector to achieve a significant improvement in detection efficiency within a limited volume.
[0076] The ultrathin flexible neutron detector based on a PIN structure silicon carbide constructed in this embodiment has an effective detection area of 64 mm². 2 Under a -50 V reverse bias condition, with a device leakage current below 5 nA, a signal shaping time set to 800 ns, and an energy threshold set to 350 keV, folding once ( Figure 3 The device shown has a thermal neutron detection efficiency of 8%, and its second-order neutron detection efficiency is 8%. Figure 4 The thermal neutron detection efficiency of the device shown is 15%, and the thermal neutron detection efficiency of the device folded five times is 32%.
[0077] Example 3:
[0078] The ultrathin flexible radiation detector based on silicon carbide in this embodiment has an MSM (metal-semiconductor-metal) structure and uses B4C as the neutron conversion material. At the same time, the device’s space compression is achieved through a stacked ingot-like folding structure.
[0079] Part 1: Fabrication of an MSM-structured ultrathin silicon carbide radiation detector unit.
[0080] In this embodiment, an intrinsic 4H-SiC epitaxial wafer with a thickness of 50 μm obtained by substrate thinning was used. Titanium / gold (Ti / Au) electrodes were prepared on the upper and lower surfaces of the 4H-SiC epitaxial layer as ohmic contact electrodes, and the electrodes were rapidly annealed at 950°C in a nitrogen atmosphere for 5 min to form ohmic contacts. The rest is the same as in Example 2.
[0081] Part 2: Fabrication of an ultrathin flexible neutron detector based on silicon carbide.
[0082] (1) The flexible substrate is made of polyimide (PI) material with a thickness of 20 μm. Its surface is subjected to plasma activation treatment to enhance the adhesion performance with silicon carbide film.
[0083] (2) The MSM detector units are transferred to a flexible substrate in an array, with the unit spacing controlled at approximately 3-7 mm to achieve high-density integration. The ultrathin silicon carbide radiation detector units of the MSM structure are connected via flexible interconnect circuits. Flexible circuits are formed on the PI substrate using silver nanowires and conductive polymer composite materials via inkjet printing technology. The circuits are designed with a serpentine or wavy structure to accommodate mechanical strain generated during subsequent folding. The units can be connected in parallel to improve the overall output signal strength and reduce equivalent noise.
[0084] (3) A neutron conversion layer was deposited on the surface of the MSM detector, using boron carbide (B4C) as the conversion material. A layer rich in boron was deposited using magnetron sputtering. 10 A B4C thin film with a boron isotope abundance ≥95% was constructed, with a thickness controlled at 2 μm. This conversion layer was achieved through... 10 B(n, α) 7 The Li reaction produces high-energy alpha particles and lithium ions, which generate electron-hole pairs in silicon carbide, thereby achieving efficient conversion of neutron signals.
[0085] (4) A flexible encapsulation protective layer with a thickness of about 6 μm is covered on the conversion layer to protect against environmental influences and improve the mechanical stability of the device, while ensuring high transmittance to neutrons.
[0086] (5) After the device fabrication is completed, the flexible detector array is spatially integrated using a stacked ingot-like folding method. See [link to documentation]. Figure 5 and Figure 6 Specifically, the device is alternately folded in both directions along a preset fold line to form a multi-layered stacked structure resembling a "gold ingot." This structure effectively superimposes the detection area within a limited space, while controlling the folding radius to avoid damaging the device's performance. Flexible insulating layers are placed between the layers, and electrode leads are reserved for signal readout.
[0087] The ultrathin flexible silicon carbide neutron detector system based on the MSM structure constructed in this embodiment has an effective detection area of 1 cm². 2 At an operating voltage of -200 V, with a device leakage current of less than 10 nA, a signal shaping time of 1 μs, and an energy threshold of 300 keV, the detection efficiency for thermal neutrons is 23%.
[0088] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention. The above embodiments are provided only for the purpose of describing the present invention and are not intended to limit the present invention. Parts not described in detail in this specification are well-known in the art and are not intended to limit the scope of the present invention. The scope of the present invention is defined by the appended claims. All equivalent substitutions and modifications made without departing from the spirit and principle of the present invention should be covered within the scope of the present invention.
Claims
1. A silicon carbide-based ultra-thin flexible neutron detector, characterized in that, include: A flexible substrate, and multiple ultrathin silicon carbide radiation detector units disposed on the flexible substrate, wherein the multiple ultrathin silicon carbide radiation detector units are spaced apart from each other to form a non-continuous distributed arrangement; A flexible circuit, which is electrically connected to each ultrathin silicon carbide radiation detector unit, includes flexible conductive traces for connecting the ultrathin silicon carbide radiation detector units in series or in parallel. A neutron conversion layer is used to convert neutrons into detectable charged particle signals; the neutron conversion layer is disposed on the surface of an ultrathin silicon carbide radiation detector unit, or the neutron conversion layer is sandwiched between two ultrathin silicon carbide radiation detector units; A flexible encapsulation protective layer covers the surface of the silicon carbide-based ultrathin flexible neutron detector.
2. The ultra-thin flexible silicon carbide based neutron detector of claim 1, wherein, The flexible conductive trace adopts an extendable trace pattern; the trace pattern of the flexible conductive trace can be any one or a combination of meandering, serpentine, wavy, zigzag or fractal structures.
3. The ultra-thin flexible silicon carbide based neutron detector of claim 1, wherein, The flexible substrate is polyimide, polyethylene terephthalate, polybutylene terephthalate or a composite flexible polymer material. The neutron conversion layer includes at least one or more mixed material layers of 10 B-containing material, Li-containing material, or H-rich material 6 The neutron conversion layer includes at least one or more mixed material layers of 1 B-containing material, Li-containing material, or H-rich material 10 The B-containing material includes B, B4C, B2O3, and BN 6 The Li-containing material includes Li, LiF, LiH, and Li2O 1 The H-rich material includes polyethylene, polypropylene, polymethyl methacrylate, paraffin wax, silicone gel, and hydrogenated polymer The ultrathin silicon carbide radiation detector unit is a Schottky structure, PN structure, PIN structure, heterojunction structure, or MSM structure.
4. The ultra-thin flexible silicon carbide based neutron detector of claim 1, wherein, The discontinuous distributed arrangement can be an array-like arrangement, a grid-like arrangement, or an island-bridge structure arrangement.
5. The ultra-thin flexible silicon carbide based neutron detector of claim 1, wherein, The ultrathin silicon carbide radiation detector unit is integrated onto a flexible substrate by transfer printing or epitaxial lift-off. The neutron conversion layer is deposited on the surface of the ultrathin silicon carbide radiation detector unit by thermal evaporation, sputtering deposition, chemical deposition or spin coating deposition; or the neutron conversion layer is made into a flexible thin layer and covered on the surface of the ultrathin silicon carbide radiation detector unit, or the neutron conversion layer is sandwiched between two ultrathin silicon carbide radiation detector units to form a layered sandwich structure.
6. The ultra-thin flexible silicon carbide based neutron detector of claim 1, wherein, The thickness of the ultrathin silicon carbide radiation detector unit is 10μm to 100μm; the thickness of the neutron conversion layer is 0.1μm to 100μm; and the thickness of the flexible encapsulation protective layer is 6μm to 10μm.
7. The ultrathin flexible neutron detector based on silicon carbide according to claim 1, characterized in that, The flexible circuit is also connected to a signal processing module, which is used to amplify, filter, and acquire data of the radiated signal.
8. The method for fabricating the ultrathin flexible neutron detector based on silicon carbide according to any one of claims 1 to 7, characterized in that, Includes the following steps: S1: Clean the surface of the flexible substrate; S2: Multiple ultrathin silicon carbide radiation detector units are integrated on a flexible substrate. The multiple ultrathin silicon carbide radiation detector units are arranged in a non-continuous distributed manner with a preset spacing. The ultrathin silicon carbide radiation detector units are connected by flexible conductive traces. S3: Prepare a neutron conversion layer; the neutron conversion layer is deposited on the surface of an ultrathin silicon carbide radiation detector unit by thermal evaporation, sputtering deposition, chemical deposition or spin coating deposition; or the neutron conversion layer is made into a flexible thin layer and covered on the surface of the ultrathin silicon carbide radiation detector unit; S4: Fabricate a flexible encapsulation protective layer covering the entire surface of the silicon carbide-based ultrathin flexible neutron detector.
9. The method for fabricating an ultrathin flexible neutron detector based on silicon carbide according to claim 8, characterized in that, The preparation method also includes the following steps: S5: Fold the entire silicon carbide-based ultrathin flexible neutron detector in a Swiss roll or ingot-like manner.
10. The application of the silicon carbide-based ultrathin flexible neutron detector according to any one of claims 1 to 7 in neutron radiation detection.