Vertical perovskite soft X-ray detector, preparation method and imaging array

Abstract

The present invention provides a vertical perovskite soft X-ray detector, a preparation method and an imaging array, which can be applied to the field of X-ray detection technology. The vertical perovskite soft X-ray detector comprises: a bottom electrode, a carrier transport layer, a perovskite light absorption layer, a passivation layer and a top electrode from bottom to top; wherein the top electrode comprises a plurality of nanoholes, the plurality of nanoholes in the top electrode penetrate the top electrode, the carrier transport layer is located at the lower interface of the perovskite light absorption layer, and the passivation layer is located at the upper interface of the perovskite light absorption layer.

Description

Technical Field

[0001] The present invention relates to the field of X-ray detection technology, and more specifically, to a vertical perovskite soft X-ray detector, a preparation method and an imaging array. Background Art

[0002] Perovskite materials have outstanding photoelectric properties, with good photoelectric response performance from the visible light band to the X-ray band, and have attracted widespread attention from researchers. In addition, perovskite has material and process advantages such as high carrier mobility and long life, good radiation stability, and solution processing, which help it achieve industrial application.

[0003] In the process of realizing the concept of the present invention, the inventors found that there are at least the following problems in the related art: the quantum efficiency of the detector in the related art is reduced and the irradiation stability is poor. Summary of the invention

[0004] In view of this, the present invention provides a vertical perovskite soft X-ray detector, a preparation method and an imaging array.

[0005] One aspect of the present invention provides a vertical perovskite soft X-ray detector, comprising:

[0006] From bottom to top: bottom electrode, carrier transport layer, perovskite light absorption layer, passivation layer and top electrode;

[0007] Among them, the above-mentioned top electrode includes multiple nanopores, the multiple nanopores in the above-mentioned top electrode penetrate the above-mentioned top electrode, the above-mentioned carrier transport layer is located at the lower interface of the above-mentioned perovskite light absorption layer, and the above-mentioned passivation layer is located at the upper interface of the above-mentioned perovskite light absorption layer.

[0008] According to an embodiment of the present invention, the passivation layer comprises a plurality of nanoholes, and the plurality of nanoholes in the passivation layer penetrate the passivation layer.

[0009] According to an embodiment of the present invention, the plurality of nanopores in the top electrode and the plurality of nanopores in the passivation layer are formed by at least one process of high vacuum thermal evaporation, chemical vapor deposition, physical vapor deposition, and spin coating.

[0010] According to an embodiment of the present invention, the perovskite light absorbing layer includes a two-dimensional perovskite layer and a three-dimensional perovskite layer.

[0011] According to an embodiment of the present invention, the thickness of the top electrode is 10-15 nm, and the top electrode includes one of a metal electrode and a non-metal electrode;

[0012] The thickness of the bottom electrode is 300-500 nm, and the bottom electrode is a metal oxide electrode.

[0013] According to an embodiment of the present invention, the thickness of the perovskite light absorbing layer is 600-700 μm, and the composition of the perovskite light absorbing layer is ABX 3 , wherein the above A is a monovalent cation.

[0014] According to an embodiment of the present invention, the above-mentioned A includes Rb + , Cs + , K + , CH 3 NH 3 + NH 2 CHN 2 + At least one of; the above B includes Pb 2+ and Sn 2+ At least one of; the above X includes Br - ,I - 、F - , Cl - 、SCN - At least one of .

[0015] According to an embodiment of the present invention, the carrier transport layer includes a hole transport layer or an electron transport layer, wherein the material of the hole transport layer includes one of 2PACz, MeO-2PACz, MeO-4PACz, CbzNaph, PTAA, PEDOT:PSS, and CuI, and the material of the electron transport layer includes SnO 2 、TiO 2 , one of ZnO.

[0016] Another aspect of the present invention provides a method for preparing the vertical perovskite soft X-ray detector as described above, comprising:

[0017] forming a patterned etched bottom electrode on the substrate;

[0018] In a nitrogen atmosphere of a glove box, a carrier transport layer and a perovskite light absorption layer are deposited on the bottom electrode by a spin coating process;

[0019] Depositing a passivation layer on the perovskite light absorption layer by at least one process selected from the group consisting of high vacuum thermal evaporation, chemical vapor deposition, physical vapor deposition, and spin coating;

[0020] The top electrode is deposited on the passivation layer by at least one process selected from the group consisting of high vacuum thermal evaporation, chemical vapor deposition, physical vapor deposition and spin coating.

[0021] Another aspect of the present invention provides an imaging array, comprising a plurality of pixel devices, each of which comprises:

[0022] Thin film transistors or complementary metal oxide semiconductors;

[0023] A vertical perovskite soft X-ray detector as described above is formed on the above-mentioned thin film transistor or the above-mentioned complementary metal oxide semiconductor, wherein the drain of the above-mentioned thin film transistor is connected to the bottom electrode of the above-mentioned vertical perovskite soft X-ray detector or the above-mentioned complementary metal oxide semiconductor.

[0024] According to the embodiments of the present invention, the nanopore structure in the top electrode can greatly reduce the absorption loss of the top electrode, and the carrier transport layer can effectively regulate the band structure of the perovskite layer and the bottom electrode, enhance the extraction of photogenerated carriers, regulate the perovskite crystallization process, reduce the bottom contact interface defects, and inhibit the non-radiative recombination of carriers. The passivation layer can reduce the surface recombination of the perovskite light absorption layer, thereby further improving the performance indicators of the vertical perovskite soft X-ray detector and helping to increase the stability of the vertical perovskite soft X-ray detector. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0026] Figure 1 A schematic diagram of a vertical perovskite soft X-ray detector according to an embodiment of the present invention is shown;

[0027] Figure 2 A flow chart showing a method for preparing a vertical perovskite soft X-ray detector according to an embodiment of the present invention is shown;

[0028] Figure 3 A schematic cross-sectional view of a single pixel device of an imaging array according to an embodiment of the present invention is shown;

[0029] Figure 4 FIG. 4 is a schematic diagram showing an equivalent circuit of a single pixel device of an imaging array according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] Below, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of concepts of the present invention.

[0031] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0032] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0033] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0034] It should be understood that when an element (such as a layer, film, region, or substrate) is described as being "on" another element, the element may be directly on the other element, or there may be intermediate elements. Moreover, in the specification and claims, when an element is described as being "connected" to another element, the element may be "directly connected" to the other element, or "connected" to the other element through a third element.

[0035] When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional views showing the device structure will not be partially enlarged according to the general scale, and the schematic views are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0036] Commercial-grade Si-based detectors in related technologies have application problems such as high process cost, low detection sensitivity, and poor irradiation stability due to their low soft X-ray attenuation coefficient and the need for a low-temperature working environment. 3 Perovskite can achieve 90% attenuation efficiency for soft X-rays with a photon energy of 1keV; under the same test conditions, the most commonly used single-crystal Si needs to be 6μm thick to achieve the same absorption rate. Therefore, perovskite soft X-ray detectors have huge development advantages.

[0037] Compared with indirect detectors, direct detectors have advantages such as high sensitivity, high spatial resolution, and high response speed due to the working principle and structural advantages of detectors. In actual working conditions, the upper transport layer (electron / hole transport layer) of perovskite PIN or NIP heterojunction detectors will be directly penetrated by soft X-rays and absorb more soft X-ray photons, which reduces the quantum efficiency of the detector and also causes poor irradiation stability of the device. In addition, perovskite detectors are further limited in imaging applications of array devices due to problems such as high dark current and low signal-to-noise ratio.

[0038] In order to realize detection and imaging applications, the detector can be further integrated with a thin film transistor (TFT) chip or a complementary metal oxide semiconductor (CMOS) chip substrate, and the readout circuit can be used to control the row and column selection of the chip and the pixel signal transmission of the detector array. Further, through electrical signal reading and amplification, digital-to-analog signal conversion, and combined with relevant software and algorithms, area array imaging can be achieved.

[0039] Compared with hard X-rays (energy range is about 10k~100keV), the photon energy of soft X-rays is between 0.1~10keV, and its penetration ability is much weaker than the former. Therefore, the device structure of the detector needs to be further optimized to improve performance.

[0040] The main problems faced in preparing perovskite detector arrays using the solution method are: it is difficult to ensure uniformity of coating over a large area, and the film has more defect states, pinholes and other unfavorable conditions, which makes it difficult to integrate the electrode and the perovskite layer, which may lead to poor contact; signal crosstalk occurs when the pixel density increases, affecting the reliability of the array data; the detector has poor irradiation stability and the imaging resolution is not high.

[0041] In addition, vertical soft X-ray detectors have been less studied before, mainly because soft X-rays have limited penetration ability. The surface 1-2μm of horizontal devices is enough to absorb most soft X-ray photons, and already has considerable quantum efficiency. However, with the development of soft X-ray imaging technology, it is necessary to further improve the detector's response speed, dark current, sensitivity and other performance indicators. Therefore, it is of great significance to develop a self-powered, vertical soft X-ray detector.

[0042] In view of this, an embodiment of the present invention provides a vertical perovskite soft X-ray detector, comprising a bottom electrode, a carrier transport layer, a perovskite light absorption layer, a passivation layer and a top electrode from bottom to top; wherein the top electrode comprises a plurality of nanoholes, the plurality of nanoholes in the top electrode penetrate the top electrode, the carrier transport layer is located at the lower interface of the perovskite light absorption layer, and the passivation layer is located at the upper interface of the perovskite light absorption layer.

[0043] Figure 1 A schematic diagram of a vertical perovskite soft X-ray detector according to an embodiment of the present invention is shown.

[0044] like Figure 1 As shown, the vertical perovskite soft X-ray detector 100 includes, from bottom to top, a bottom electrode 110 , a carrier transport layer 120 , a perovskite light absorption layer 130 , a passivation layer 140 and a top electrode 150 .

[0045] The top electrode 150 includes a plurality of nanoholes, and the plurality of nanoholes in the top electrode 150 penetrate the top electrode 150 . The carrier transport layer 120 is located at the lower interface of the perovskite light absorption layer 130 , and the passivation layer 140 is located at the upper interface of the perovskite light absorption layer 130 .

[0046] According to an embodiment of the present invention, the top electrode 150 includes a plurality of nanopores, and the plurality of nanopores in the top electrode 150 penetrate the top electrode 150. The plurality of nanopores in the top electrode 150 can be formed by high vacuum thermal evaporation (vacuum degree higher than 4×10 -4 The top electrode 150 is formed by at least one of the following processes: chemical vapor deposition, physical vapor deposition, and spin coating. The thickness of the top electrode 150 is 10-15 nm, and the top electrode 150 can be a metal electrode or a non-metal electrode.

[0047] According to an embodiment of the present invention, the material of the top electrode 150 can be one of metal electrodes such as gold (Au), silver (Ag), chromium (Cr), titanium (Ti), etc.; it can also be a non-metal electrode such as carbon (C). Taking into account the soft X-ray absorption loss of the top electrode 150 and the stability of the electrode and the perovskite interface, Au or Ag can be selected and formed into a nanoporous structure, which can greatly reduce the absorption loss of the top electrode 150.

[0048] According to an embodiment of the present invention, the design of the nanopore top electrode 150 can greatly reduce the absorption of soft X-rays by the top electrode 150, achieve balanced optimization of the "dead zone" attenuation and photocurrent extraction of the device, and improve the detection rate of soft X-rays by the vertical perovskite soft X-ray detector 100 of the embodiment of the present invention.

[0049] According to an embodiment of the present invention, a passivation layer 140 is deposited on the surface of the perovskite light absorption layer 130 to reduce its surface recombination, thereby further improving the performance indicators of the vertical perovskite soft X-ray detector 100. In addition to considering the interface matching, process compatibility and irradiation stability of the perovskite light absorption layer 130, the material selection of the passivation layer 140 should also be based on the weak soft X-ray absorption ability to reduce photon absorption. For example, it can be Si 3 N 4 、Al 2 O 3The material of the passivation layer 140 should have a low absorption rate, reduce the surface defects of the perovskite and have little effect on the charge transfer of the original device.

[0050] According to an embodiment of the present invention, the passivation layer 140 includes a plurality of nanopores, and the plurality of nanopores in the passivation layer 140 penetrate the passivation layer 140. The nanopore structure in the passivation layer 140 can reduce the absorption loss of the passivation layer 140 to soft X-rays. The plurality of nanopores in the passivation layer 140 can be formed by at least one process of high vacuum thermal evaporation, chemical vapor deposition, physical vapor deposition, and spin coating. The specific formation process can be selected according to the material of the passivation layer 140, for example, Al 2 O 3 The passivation layer 140 of material may be formed by spin coating nanoparticles.

[0051] According to an embodiment of the present invention, the passivation layer 140 is made of Si 3 N 4 、Al 2 O 3 , PMMA. By selecting the material of the passivation layer 140 and adjusting the appropriate thickness, the absorption of the "dead zone" of the device can be effectively reduced; the contact between the electrode and the perovskite is physically blocked, the chemical reaction and performance degradation at the interface between the two under the working voltage are suppressed, and the ion migration of the perovskite is suppressed, thereby improving the working stability of the device. For the vertical soft X-ray detector 100, a suitable passivation layer 140 material is selected and its thickness is optimized. On the basis of reducing the absorption of the "dead zone" of the device, the charge collection ability of the device is optimized, thereby achieving better detection performance.

[0052] According to an embodiment of the present invention, the perovskite light absorption layer 130, as a soft X-ray absorption layer, may be a lead-based perovskite material. In order to further reduce surface defects, improve stability, and promote the extraction of photogenerated carriers, the perovskite light absorption layer 130 may include a two-dimensional perovskite layer and a three-dimensional perovskite layer. The two-dimensional perovskite may be at least one of the Ruddlesden-Popper and Dion-Jacobson configurations, and the three-dimensional perovskite may be a cubic phase. The perovskite light absorption layer 130 combines the advantages of bandgap regulation and stability of two-dimensional perovskites, and the advantages of high absorption and high charge mobility of three-dimensional perovskites.

[0053] According to an embodiment of the present invention, the thickness of the perovskite light absorbing layer 130 is 600-700 μm. Compared with the commonly used single crystal Si, the device thickness can be reduced. The composition of the perovskite light absorbing layer 130 is ABX 3 , wherein A is a monovalent cation, and A may include Rb + , Cs + , K + , CH3 NH 3 + NH 2 CHN 2 + At least one of; B may include Pb 2+ and Sn 2+ At least one of; X may include Br - ,I - 、F - , Cl - 、SCN - At least one of .

[0054] According to an embodiment of the present invention, the carrier transport layer 120 includes one of a hole transport layer and an electron transport layer, wherein the material of the hole transport layer includes one of 2PACz, MeO-2PACz, MeO-4PACz, CbzNaph, PTAA, PEDOT:PSS, and CuI, and the material of the electron transport layer includes SnO 2 、TiO 2 , one of ZnO.

[0055] According to an embodiment of the present invention, the carrier transport layer 120 can adjust the band structure at the interface to enhance the extraction of photocarriers; in addition, it can also regulate the crystallization process of the perovskite film, optimize the contact between the light absorption layer and the bottom electrode 110, effectively suppress the generation of defects, and achieve device noise suppression and response speed improvement.

[0056] According to an embodiment of the present invention, the thickness of the bottom electrode 110 is 300-500 nm, and the bottom electrode 110 is a metal oxide electrode, such as ITO, FTO, etc. The metal oxide electrode has the advantages of excellent conductivity, matching with the perovskite energy level, good light transmittance and good stability.

[0057] In the vertical perovskite soft X-ray detector 100 of the present invention, only a carrier transport layer 120 is arranged between the bottom electrode 110 and the perovskite light absorption layer 130 at the bottom, and there is no need to arrange a hole transport layer or an electron transport layer between the perovskite light absorption layer 130 and the top electrode 150, thereby reducing the thickness of the vertical perovskite soft X-ray detector 100 and avoiding the problem of poor stability caused by the hole transport layer or the electron transport layer arranged in the upper layer when detecting soft X-rays; on the contrary, the present invention uses a passivation layer 140 between the perovskite light absorption layer 130 and the top electrode 150, thereby improving the stability of the vertical perovskite soft X-ray detector 100.

[0058] Figure 2 A flow chart of a method for preparing a vertical perovskite soft X-ray detector according to an embodiment of the present invention is shown.

[0059] like Figure 2 As shown, the method includes operations S210 to S240.

[0060] In operation S210, a pattern-etched bottom electrode is formed on a substrate.

[0061] In operation S220 , a carrier transport layer and a perovskite light absorption layer are deposited on the bottom electrode by a spin coating process in a nitrogen atmosphere of a glove box.

[0062] In operation S230 , a passivation layer is deposited on the perovskite light absorbing layer by at least one process selected from the group consisting of high vacuum thermal evaporation, chemical vapor deposition, physical vapor deposition, and spin coating.

[0063] In operation S240 , a top electrode is deposited on the passivation layer by at least one process selected from the group consisting of high vacuum thermal evaporation, chemical vapor deposition, physical vapor deposition, and spin coating.

[0064] According to an embodiment of the present invention, a patterned etched bottom electrode can be formed on a substrate, for example, it can be FTO conductive glass, and the patterned etched FTO conductive glass is ultrasonically cleaned. The FTO conductive glass is placed in deionized water, acetone, isopropanol and ethanol solvents in turn, and ultrasonically cleaned in each solvent for 10 minutes. Then, nitrogen is used to blow dry the solvent on the surface and placed in a UV ozone cleaning machine, and UV ozone cleaning is set at 30°C for 20 minutes.

[0065] According to an embodiment of the present invention, a carrier transport layer and a perovskite light absorption layer can be deposited in a nitrogen atmosphere in a glove box by a spin coating process. 0.05 Cs 0.05 MA 0.05 FA 0.85 Pb(I 0.95 Br 0.05 ) 3 Take perovskite as an example: prepare 0.5mg / mL MeO-2PACz ethanol solution, add 100μL MeO-2PACz solution on FTO glass, and set the spin coating parameters to: speed 4000rpm, time 30s. After spin coating, place the FTO glass on a hot plate and anneal at 100℃ for 8 minutes to form a FTO / MeO-2PACz substrate.

[0066] According to the molar ratio of the perovskite components, CsI, RbI, MABr, FAI, and PbI were weighed respectively. 2 and PbBr 2The powder was dissolved in a mixed solution of DMF and DMSO (DMF:DMSO=4:1) at a concentration of 1.5M. It was then heated and stirred at 50°C for 2 hours using a magnetic stirrer before use. 50μL of the perovskite precursor solution was added dropwise onto the FTO / MeO-2PACz substrate, and the gel coater was set to a multi-step spin coating mode: the first step was 1000rpm, 10s, 1000rpm / s; the second step was 4000rpm, 30s, 4000rpm / s. When the second step of spin coating was 10 seconds in the countdown, 150μL of anti-solvent chlorobenzene was added dropwise at a uniform speed. The sample was then placed on a 100°C hot plate for annealing for 20 minutes.

[0067] Prepare a perovskite heterojunction to obtain a perovskite light absorbing layer and chemically passivate the upper surface of the perovskite light absorbing layer. For example: prepare an isopropanol solution of 1 mg / mL PEAI and 0.5 mg / mL MAI, heat and stir at 70°C for 2 hours, and then filter to obtain a mixed solution of PEAI and MAI. After the perovskite film is annealed and cooled, add 100 μL of the PEAI and MAI mixed solution, and spin coat at 5000 rpm and 60 s to finally form a perovskite heterojunction.

[0068] The top electrode is deposited by high vacuum thermal evaporation process. For example: -4 Pa, 10nm thick Au was evaporated at a rate of 0.001nm / s, and the substrate temperature was below 50℃ after completion.

[0069] Figure 3 A schematic cross-sectional view of a single pixel device of an imaging array according to an embodiment of the present invention is shown.

[0070] like Figure 3 As shown, the imaging array includes a plurality of pixel devices, each of which includes: a thin film transistor, that is, Figure 3 a is a structure formed by the gate, source, drain, gate insulating layer and active layer on the left half of the glass substrate; a vertical perovskite soft X-ray detector as in the embodiment of the present invention formed on the thin film transistor, that is, Figure 3 The structure formed by the top electrode, passivation layer, perovskite light absorption layer, carrier transport layer and bottom electrode in the right half of a on the glass substrate is connected to the bottom electrode of the vertical perovskite soft X-ray detector, and then output to the readout circuit for signal reading.

[0071] Each pixel device may also include: a complementary metal oxide semiconductor, namely Figure 3 The structure formed by the source, drain, gate electrode, insulating layer, P well and P-Si substrate in the lower half of b; the vertical perovskite soft X-ray detector as in the embodiment of the present invention formed on the complementary metal oxide semiconductor, that is, Figure 3The structure formed by the top electrode, passivation layer, perovskite light absorption layer, carrier transport layer and bottom electrode in the upper right part of b. Among them, the drain of the complementary metal oxide semiconductor is connected to the bottom electrode of the vertical perovskite soft X-ray detector, and then output to the readout circuit signal reading.

[0072] Figure 4 FIG. 4 is a schematic diagram showing an equivalent circuit of a single pixel device of an imaging array according to an embodiment of the present invention.

[0073] like Figure 4 As shown, the thin film transistor is the transistor part in the figure, and the vertical perovskite soft X-ray detector is the photodiode in the circuit.

[0074] According to an embodiment of the present invention, a spin coating process can be used to deposit a carrier transport layer, a perovskite light absorption layer and a top electrode on a thin film transistor (TFT) chip or a complementary metal oxide semiconductor chip in multiple steps to prepare an imager. Using the carrier transport layer as the lower interface of the perovskite has the advantages of reducing interface defects, regulating perovskite crystallization, reducing film defects and holes, etc., which can effectively improve the detection limit, sensitivity and uniformity of the imager.

[0075] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. In this regard, each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions. It can be understood by those skilled in the art that the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways, even if such a combination or combination is not explicitly recorded in the present invention. In particular, without departing from the spirit and teachings of the present invention, the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways. All these combinations and / or combinations fall within the scope of the present invention.

[0076] The embodiments of the present invention are described above. However, these embodiments are only for the purpose of illustration, and are not intended to limit the scope of the present invention. Although each embodiment is described above, it does not mean that the measures in each embodiment cannot be used in combination advantageously. Without departing from the scope of the present invention, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A vertical perovskite soft X-ray detector, characterized in that: The vertical perovskite soft X-ray detector comprises: From bottom to top: bottom electrode, carrier transport layer, perovskite light absorption layer, passivation layer and top electrode; Among them, the top electrode includes a plurality of nanoholes, the plurality of nanoholes in the top electrode penetrate the top electrode, the carrier transport layer is located at the lower interface of the perovskite light absorption layer, and the passivation layer is located at the upper interface of the perovskite light absorption layer; the passivation layer includes a plurality of nanoholes, the plurality of nanoholes in the passivation layer penetrate the passivation layer, the plurality of nanoholes in the passivation layer are used to reduce the absorption loss of the passivation layer to soft X-rays, and the passivation layer includes at least one of Si3N4, Al2O3, and PMMA.

2. The vertical perovskite soft X-ray detector according to claim 1, characterized in that: The multiple nanopores in the top electrode and the multiple nanopores in the passivation layer are formed by at least one process of high vacuum thermal evaporation, chemical vapor deposition, physical vapor deposition, and spin coating.

3. The vertical perovskite soft X-ray detector according to claim 1, characterized in that: The perovskite light absorbing layer includes a two-dimensional perovskite layer and a three-dimensional perovskite layer.

4. The vertical perovskite soft X-ray detector according to any one of claims 1 to 3, characterized in that: The thickness of the top electrode is 10-15 nm, and the top electrode includes one of a metal electrode and a non-metal electrode; The thickness of the bottom electrode is 300-500 nm, and the bottom electrode is a metal oxide electrode.

5. The vertical perovskite soft X-ray detector according to any one of claims 1 to 3, characterized in that: The thickness of the perovskite light absorbing layer is 600-900 μm, and the component of the perovskite light absorbing layer is ABX3, wherein A is a monovalent cation.

6. The vertical perovskite soft X-ray detector according to claim 5, characterized in that: The A includes Rb + , Cs + , K + 、CH3NH3 + 、NH2CHNH2 + At least one of; said B includes Pb 2+ and Sn 2+ At least one of; said X comprises Br - ,I - 、F - , Cl - 、SCN - At least one of .

7. The vertical perovskite soft X-ray detector according to any one of claims 1 to 3, characterized in that: The carrier transport layer includes a hole transport layer or an electron transport layer, wherein the material of the hole transport layer includes one of 2PACz, MeO-2PACz, MeO-4PACz, CbzNaph, PTAA, PEDOT:PSS, and CuI, and the material of the electron transport layer includes one of SnO2, TiO2, and ZnO.

8. A method for preparing a vertical perovskite soft X-ray detector according to any one of claims 1 to 7, characterized in that: The preparation method comprises: forming a patterned etched bottom electrode on the substrate; In a nitrogen atmosphere of a glove box, a carrier transport layer and a perovskite light absorption layer are deposited on the bottom electrode by a spin coating process; Depositing a passivation layer on the perovskite light absorbing layer by at least one process selected from the group consisting of high vacuum thermal evaporation, chemical vapor deposition, physical vapor deposition, and spin coating; A top electrode is deposited on the passivation layer by at least one process selected from the group consisting of high vacuum thermal evaporation, chemical vapor deposition, physical vapor deposition, and spin coating.

9. An imaging array, characterized in that: The imaging array includes a plurality of pixel devices, each of which includes: Thin film transistors or complementary metal oxide semiconductors; A vertical perovskite soft X-ray detector as described in any one of claims 1 to 7 formed on the thin film transistor or the complementary metal oxide semiconductor, wherein the drain of the thin film transistor or the complementary metal oxide semiconductor is connected to the bottom electrode of the vertical perovskite soft X-ray detector.

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