Perovskite photodetector array with curved focal plane and methods and applications

Abstract

The application discloses a perovskite photoelectric detector array with a curved focal plane, a method and an application, which comprise a flexible supporting substrate (1) and a focal plane array (2), wherein the flexible supporting substrate (1) is made of a transparent flexible material, and the curved shape of the flexible supporting substrate (1) is consistent with that of the focal plane array (2); and the light-absorbing layer and the charge transport layer material in the focal plane array (2) are prepared on the surface of the flexible supporting substrate (1) layer by layer through a spin coating or evaporation process. The application effectively corrects the field curvature aberration without increasing the complexity of an optical system. The light-absorbing layer is made of perovskite material, and compared with a traditional silicon-based curved detector array, the perovskite photoelectric detector array has the advantages of low production cost, simple process, large effective imaging area, high pixel density and high resolution.

Description

Technical Field

[0001] This invention belongs to the field of visible light detection, specifically referring to a perovskite photodetector array with a curved focal plane suitable for curved surface imaging, its fabrication method, and its application. Background Technology

[0002] Visible photodetectors are devices that convert light signals in the 400-780nm wavelength range into electrical signals. They are widely used in imaging, measurement, communication, medical monitoring, industrial automation, and many other fields. Reducing aberrations and improving image quality have always been the core pursuits in the development of visible light imaging detection technology, which is especially crucial in the fields of large field of view and high resolution detection.

[0003] In their latest paper, "Flexible soft X-ray imagesensors based on metal halide perovskites with high quantum efficiency," Professor Hu Qin's research group at the University of Science and Technology of China achieved a breakthrough in quantum efficiency for perovskite soft X-ray detectors by manipulating defects in perovskite thin films and designing PIN vertical device structures. While similar research has fabricated perovskite detectors on flexible substrates, primarily focusing on improving their detection efficiency and sensitivity, aberrations have not been adequately considered when using these detector arrays for imaging. In contrast, this invention focuses on visible light imaging, aiming to improve the imaging quality of detector arrays, particularly optimizing for the field curvature aberration problem commonly found in imaging systems. Furthermore, this invention prioritizes the design and implementation of the curved structure of the detector array over pursuing extreme flexibility. After precise shaping of the flexible perovskite photodetector array, it can be fixed without subsequent repeated shape adjustments or folding operations.

[0004] Field curvature (image field bending) is a widespread aberration in optical systems. When a plane is imaged through an optical system such as a single lens, although all object points will appear as sharp images behind the lens, the image plane formed by these sharp images is curved; that is, the focal plane of the optical system is curved. Given that existing detector arrays generally adopt planar structures, corresponding aberration corrections must be performed on the optical system to achieve efficient matching with the curved focal plane. Field curvature aberration is significantly aggravated as the field of view increases; therefore, field curvature correction becomes particularly difficult in large field-of-view, high-resolution imaging applications. To correct field curvature aberration, complex optical systems with careful design and precision manufacturing are typically employed, including using multi-lens combinations instead of single-lens designs and using aspherical lenses instead of spherical lenses. However, this traditional approach inevitably introduces additional optical losses and leads to an increase in the size, weight, and cost of the entire detection system, which poses significant limitations in many specific applications such as micro-drones and endoscopes.

[0005] Integrating field curvature correction into the detector array is an innovative solution for reducing aberrations while effectively avoiding the complexity of the optical system. Inspired by the structure of the human retina in bionics, transforming the detector array design from planar to curved is a direct and effective aberration correction strategy. Currently, research on curved detector arrays mainly focuses on traditional inorganic semiconductor silicon. Silicon is a rigid material, and its low mechanical damage threshold limits the bending adaptability of the detector, preventing the entire detector from being directly bent into a curved shape. Conventional methods construct curved surfaces by connecting multiple small planar detectors, but due to the limitations of the detectors' own bending capabilities, hollowing out the joints is required, resulting in a discontinuous "pseudo-curved surface" formed by splicing multiple planes into the detector array. Furthermore, the hollowing out at the joints reduces the effective imaging area, limiting the pixel density and resolution of the detector array. Therefore, there is an urgent need to develop an inherently flexible visible light detector to fabricate a truly curved detector array.

[0006] Organic-inorganic hybrid lead halide perovskite materials are considered ideal next-generation visible light detection materials due to their ability to be prepared by low-temperature solution methods, high visible light absorption coefficient, and high carrier mobility. More importantly, these materials can be easily fabricated on flexible substrates, endowing perovskite detectors with high mechanical flexibility and bending adaptability. Therefore, curved detector arrays developed based on perovskite materials have significant research value and application prospects. Summary of the Invention

[0007] This invention aims to overcome the limitations of traditional visible light imaging technology, which relies on complex optical systems to correct field curvature aberrations. By introducing a detector structure with a curved focal plane, direct aberration compensation is achieved. This improves the resolution of the imaging detection system over a large field of view while significantly reducing the complexity of the optical system design. Furthermore, compared to existing silicon-based curved detector arrays, this invention utilizes a novel perovskite material with excellent mechanical flexibility, simplifying the fabrication process and eliminating the need for hollowing or splicing steps. This ensures the detector array is a single, continuous curved surface, demonstrating significant technological advantages and application prospects.

[0008] The technical solution of this invention:

[0009] A perovskite photodetector array with a curved focal plane includes a flexible support substrate (1) and a shaped focal plane array (2). The flexible support substrate (1) is made of indium tin oxide (ITO) deposited as a transparent flexible substrate, including polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA), thermoplastic polyurethane rubber (TPU), polystyrene (PS), or a novel thermoplastic elastomer (SEBS). The curved shape of the flexible support substrate (1) is consistent with that of the shaped focal plane array (2).

[0010] The perovskite photodetector array with curved focal plane, wherein the light-absorbing layer and charge transport layer materials in the shaped focal plane array (2) are prepared on the surface of the supporting substrate (1) by a layer-by-layer spin coating method.

[0011] The perovskite photodetector array comprises electrodes, a first charge transport layer, a second charge transport layer, and a perovskite layer; wherein the perovskite layer is a thin film formed of low-dimensional or three-dimensional perovskite, and the low-dimensional perovskite is any one or more combinations of zero-dimensional, one-dimensional, and two-dimensional; the first charge transport layer is one or more combinations of hole transport layer and electron blocking layer, and the second charge transport layer is one or more combinations of electron transport layer and hole blocking layer; or the first charge transport layer is one or more combinations of electron transport layer and hole blocking layer, and the second charge transport layer is one or more combinations of electron transport layer and hole blocking layer.

[0012] The perovskite photodetector array described herein uses poly(3,4-ethylenedioxythiophene / polystyrene sulfonate), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid, [2-(9H-carbazole-9-yl)ethyl]phosphonic acid, 2,2',7,7'-tetra[N,N-di(4-methoxyphenyl)amino]-9,9'-spirodifluorene, tin oxide, titanium oxide, C60 derivatives, C70 derivatives, C60, copper bath, and doped 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone, or a combination of several of these materials.

[0013] The perovskite photodetector array described herein, wherein the perovskite layer is prepared by the following method: spin-coating a perovskite precursor solution onto the charge transport layer; the spin-coating speed is 1000-9000 rpm, and after spin-coating for 2-180 seconds, annealing is performed at 20-150°C for 1-150 minutes; wherein the perovskite precursor solution is a mixture of metal cations, halogen or pseudohalogen anions and monovalent organic cations dissolved in a solvent, and the mass concentration of the solute in the solution is 15-45%; wherein the solvent is any one or more combinations of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone.

[0014] The perovskite photodetector array wherein the metal cation is one or more combinations of lead, rubidium, cesium, potassium, and sodium; the halogen or pseudohalogen anion includes one or more combinations of fluorine, chlorine, bromine, iodine, and thiocyanate; and the monovalent organic cation includes one or more combinations of methylamine, formamidinium, fluoroanisidine, fluorophenylethylamine, chloroanisidine, chlorophenylethylamine, bromoanisidine, and bromophenylethylamine.

[0015] The perovskite photodetector array, wherein the photodetector comprises, from top to bottom, a transparent electrode, a first charge transport layer, a perovskite layer, a second charge transport layer and a metal electrode, or from top to bottom, a transparent electrode, a second charge transport layer, a perovskite layer, a first charge transport layer and a metal electrode.

[0016] The perovskite photodetector array wherein the transparent electrode is a flexible indium tin oxide-polyethylene terephthalate; and the metal electrode is any one or a combination of gold, copper, chromium, silver, aluminum, and lithium fluoride.

[0017] A method for fabricating any of the perovskite photodetector arrays described above includes the following steps:

[0018] 1) Fix a thin, flexible support substrate onto a transparent, rigid substrate;

[0019] 2) A perovskite photodetector is obtained by spin-coating a hole transport layer, a perovskite active layer, and an electron transport layer on a flexible support substrate and then evaporating electrodes. Finally, a perovskite detector array with mechanical flexibility is obtained by removing the transparent rigid substrate.

[0020] 3) The perovskite detector array is placed on a flexible support substrate (1) with a certain curvature, and shaped. After shaping, the shape is promoted by glue, and finally the shaped flexible perovskite photodetector array is obtained.

[0021] The method specifically includes the following steps:

[0022] 1) Fabrication of transparent electrodes: A clean indium tin oxide-polyethylene terephthalate flexible substrate is subjected to surface oxygen plasma treatment;

[0023] 2) Preparation of the first charge transport layer: Spin-coat the first charge transport layer solution onto the treated substrate at a speed of 3000-6000 rpm for 30-60 seconds, and then anneal at 100-150℃ for 10-30 minutes.

[0024] 3) Preparation of the perovskite layer: A perovskite precursor solution is spin-coated onto the first charge transport layer, wherein the perovskite precursor solution is prepared by dissolving a mixture of metal cations, halogen or pseudohalogen anions and monovalent organic cations in a solvent, with the mass concentration of the solute in the solution being 15-50%; the solvent is any one or a combination of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone.

[0025] 4) Preparation of the second charge transport layer: spin-coating or vapor-depositing the second charge transport layer onto the perovskite layer;

[0026] 5) Fabrication of metal electrodes: Metal is deposited on the second charge transport layer by vapor deposition.

[0027] Or it may include the following steps:

[0028] 1) Fabrication of transparent electrodes: A clean indium tin oxide-polyethylene terephthalate flexible substrate is subjected to surface oxygen plasma treatment;

[0029] 2) Preparation of the second charge transport layer: The second charge transport layer is spin-coated on the treated substrate at a speed of 3000-5000 rpm for 30-60 seconds, followed by annealing at 100-150℃ for 20-60 minutes.

[0030] 3) Preparation of the perovskite layer: A perovskite precursor solution is spin-coated onto the second charge transport layer, wherein the perovskite precursor solution is prepared by dissolving a mixture of metal cations, halogen or pseudohalogen anions and monovalent organic cations in a solvent, with the mass concentration of the solute in the solution being 15-50%; the solvent is any one or more combinations of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone.

[0031] 4) Preparation of the first charge transport layer: Spin-coat the first charge transport layer solution onto the perovskite layer at a speed of 3000-5000 rpm for 30-60 seconds;

[0032] 5) Fabrication of metal electrodes: Metal is deposited on the first charge transport layer by vapor deposition.

[0033] The present invention has the following beneficial effects:

[0034] 1. Effective correction of field curvature aberration was achieved without increasing the complexity of the optical system.

[0035] 2. A novel perovskite material prepared by solution method is used to prepare photoelectric detection arrays, which has a lower production cost.

[0036] 3. The photoelectric detection array adopts a single continuous curved surface design, which has a large effective imaging area and high pixel density and resolution.

[0037] This invention has significant application prospects in the following fields:

[0038] 1. Medical field: Endoscopes require observation of a large field of view. Curved photodetector arrays can be flexibly adapted to different lenses. While correcting field curvature aberrations and ensuring imaging accuracy, the endoscope structure remains compact to adapt to the complex spatial structure inside the human body, reducing patient discomfort during examination and providing reliable technical support for minimally invasive surgery and disease diagnosis.

[0039] 2. In the field of astronomy: Curved photodetector arrays can be efficiently matched with large astronomical telescopes with a wide field of view, reducing light loss and field curvature aberration, thereby capturing faint signals from distant celestial objects more clearly and helping astronomers observe fainter and more distant celestial objects.

[0040] 3. Automotive sector: In automotive surround view systems and autonomous driving assistance systems, curved surface sensors can provide a wider and clearer field of view, enhance the ability to detect obstacles in the surrounding environment, improve driving safety, and promote the development of autonomous driving technology. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of a perovskite photodetector array suitable for curved surface imaging in this invention, wherein 1 is a supporting substrate and 2 is a shaped focal plane array;

[0042] Figure 2 This is a schematic diagram of the structure of each detector in the perovskite photodetector array of the present invention; a corresponds to the first preparation method in Example 3, and b corresponds to the second preparation method in Example 3;

[0043] Figure 3 This is a schematic diagram of the optical path principle when the perovskite photodetector array in this invention is applied to imaging;

[0044] Figure 4 This is a comparison diagram of a perovskite photodetector array and a silicon-based photodetector array suitable for curved surface imaging in this invention; wherein, a (perovskite) and b (silicon-based) are a comparison of the array bending method, and c (perovskite) and d (silicon-based) are a comparison of the detector arrangement method.

[0045] Figure 5 These are schematic diagrams of the imaging optical paths of the plano-convex lens under different fields of view in Embodiments 1 and 2 provided;

[0046] Figure 6 This refers to the magnitude of field curvature aberration in plano-convex lens imaging under different fields of view in the provided embodiment 1;

[0047] Figure 7 This refers to the magnitude of field curvature aberration in plano-convex lens imaging under different fields of view in the provided embodiment 2;

[0048] Figure 8 This is the absorption spectrum of the perovskite active layer in Example 3 provided;

[0049] Figure 9 This is a comparison chart of the responsivity of the perovskite photodetector and the commercially available high-performance silicon-based visible light detector (Hamamatsu S1087, Japan) under self-driven operation in Example 1.

[0050] Figure 10 This is a method for fabricating perovskite photodetector arrays suitable for curved surface imaging. Detailed Implementation

[0051] The present invention will be described in detail below with reference to specific embodiments.

[0052] The following uses Figure 3 The lens optical path principle analysis shown illustrates the advantages of the perovskite photodetector array suitable for curved surface imaging in this invention compared to ordinary planar photodetector arrays.

[0053] When imaging planar objects using simple optical systems such as single lenses, as the field of view widens, the focal point of the incident light gradually shifts towards the lens relative to the zero-field focal point, causing the final imaging surface to gradually transform from an ideal plane into a curved surface. Therefore, clear imaging becomes particularly difficult at the edges of the field of view. When the deviation between the focal point and the planar focal plane exceeds the depth of focus, distortion and blurring occur at the image edges (corresponding to the edge region of the detector array), failing to meet the requirements for high-resolution imaging. However, by employing the perovskite detector array of this invention, obliquely incident light can be uniformly focused onto the curved detector surface, thereby compensating for aberrations and significantly improving distortion.

[0054] The following uses Figure 4 The comparison diagrams shown illustrate the advantages of the perovskite photodetector array suitable for curved surface imaging in this invention compared to curved silicon-based detector arrays.

[0055] Given the rigidity of silicon, directly molding it into a curved structure is not feasible. Conventional curved silicon-based detector arrays are mostly constructed by splicing together several small planar detectors. Even ignoring the complexity of the design and splicing process, and considering only the performance of the final detector array, this approach still has two major drawbacks: 1. The resulting curved surface is essentially a combination of multiple planes, a discontinuous "pseudo-curved surface." Only when the planar detectors are densely arranged can this "pseudo-curved surface" approximate a real curved surface relatively well. When the field curvature correction requirement is high (i.e., the focal plane curvature is large), the construction of the "pseudo-curved surface" is significantly limited. 2. The detectors themselves have limited bending capabilities. To give the array a large curvature, it is necessary to implement hollowing-out treatment at the detector connection points and use flexible materials for connection. With the pixel size (detector area) remaining unchanged, this will lead to a reduction in the number of detectors that can be configured in the same area, thereby reducing the detector array resolution. Due to the high mechanical flexibility of perovskite materials, the perovskite detector array in this invention is a continuous curved surface that can be flexibly bent to match the required curvature scenarios. The arrangement of the detectors is free, and there is no need for hollowing-out or connection treatment.

[0056] The present invention will be described in detail below with reference to specific embodiments.

[0057] Example 1

[0058] In this specific embodiment, the detector array discussed in this invention is specially designed to accommodate a single plano-convex lens made of NBK glass with a diameter of 12.7 mm and a focal length of 5 cm. Traditionally, standard planar detector arrays used with this plano-convex lens have a target surface size of 7.2 mm × 5.4 mm. The specific implementation of the structure and fabrication method of this invention will be further described below with reference to the accompanying drawings, and the problems encountered when using a standard planar detector array and the necessity of using a curved detector array will be analyzed. For ease of description, only the curvature of the detector array in the long axis direction is considered here, i.e., the image plane height of the maximum field of view in the long axis direction is 3.6 mm.

[0059] A thin flexible support substrate is fixed onto a rigid quartz substrate using a small amount of UV-curable adhesive. After a preparation process consistent with normal procedures, a perovskite photodetector is fabricated on the flexible substrate. Once the UV-curable adhesive is completely removed, the rigid quartz substrate can be peeled off to form a perovskite detector array with mechanical flexibility.

[0060] The perovskite detector array is placed on a flexible PDMS mold with a certain curvature and shaped. After shaping, it is fixed by UV curing material and UV irradiation. Finally, the shaped perovskite photodetector array is taken out.

[0061] like Figure 5 and Figure 6 As shown, when the image height is set to 3.6 mm, the field of view is approximately 4 degrees, and the field curvature is less than 1 mm. Although the absolute value is not large, there is still room for improvement. To further reduce the field curvature and improve the imaging quality, the curved detector array of this invention can be used to replace the conventional planar detector array. Since the required correction amount is small, the curvature requirement of this curved detector array is low, and the shaping difficulty is small. Therefore, it is expected to reduce the field curvature to near zero, achieving extremely high imaging quality.

[0062] Example 2

[0063] In this specific embodiment, the detector array discussed in this invention is specially designed to accommodate a single plano-convex lens made of NBK glass with a diameter of 12.7 mm and a focal length of 5 cm. Traditionally, standard planar detector arrays used with this plano-convex lens have a target surface size of 50 mm × 50 mm. The specific embodiments of the structure and fabrication method of this invention will be further described below with reference to the accompanying drawings, and the problems encountered when using a standard planar detector array and the necessity of using a curved detector array will be analyzed. For ease of description, only the curvature of the detector array in the long axis direction is considered here, i.e., the image plane height of the maximum field of view in the long axis direction is 25 mm.

[0064] A thin flexible support substrate is fixed onto a rigid quartz substrate using a small amount of UV-curable adhesive. After a preparation process consistent with normal procedures, a perovskite photodetector is fabricated on the flexible substrate. Once the UV-curable adhesive is completely removed, the rigid quartz substrate can be peeled off to form a perovskite detector array with mechanical flexibility.

[0065] The perovskite detector array is placed on a PMMA flexible mold with a certain curvature and shaped. After shaping, it is characterized by UV curing material and UV irradiation. Finally, the shaped perovskite photodetector array is taken out.

[0066] like Figure 5 and Figure 6 As shown, when the image height is set to 25mm, the field of view is close to 40 degrees, and the field curvature exceeds 10mm. Compared with Embodiment 1, due to the larger detector target size and wider field of view, the amount of field curvature that needs to be corrected increases accordingly. If a planar detector array is relied upon, the imaging quality will significantly decrease, especially the blurring of the image under a large field of view will be exacerbated. Using the curved detector array in this invention to replace the conventional planar detector array can effectively reduce the field curvature. Given the high degree of curvature required, the shaping effect of the actual curved detector array may not completely meet the design expectations, but due to the large initial field curvature, even if the shaping effect does not fully meet the requirements, the improvement in image quality will still be very significant.

[0067] Example 3

[0068] The fabrication of a perovskite photodetector array suitable for curved surface imaging is as follows (( Figure 2 -a)):

[0069] 1) Substrate treatment: The clean indium tin oxide-polyethylene terephthalate flexible substrate is subjected to surface oxygen plasma treatment;

[0070] 2) Preparation of hole transport layer (i.e. first charge transport layer): Spin-coat a PTAA solution layer (2-10 mg / ml dissolved in chlorobenzene solvent, doped with 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone (F4-TCNQ), doping concentration of 0.4 mg / ml) onto the treated substrate at a spin speed of 5000 rpm for 30 seconds, followed by annealing at 100°C for 10 minutes.

[0071] 3) Preparation of the perovskite layer (light-absorbing layer): After preheating the substrate to 100℃, a perovskite precursor solution (methylamine chloride, lead iodide, m-fluorobenzylamine iodide, rubidium iodide) with a molar ratio of 2.2:3.5:4:0.03 and a 30% mass concentration dissolved in DMF solvent was spin-coated onto the first charge transport layer. The spin-coating speed was 5000 rpm. After spin-coating for 20 seconds, the substrate was annealed at 80-100℃ for 10 minutes.

[0072] 4) Fabrication of the electron transport layer (i.e., the second charge transport layer): The electron transport layer is fabricated on the perovskite layer under a vacuum of 10... -7 During the Torr process, C60 with a wavelength of 60 nm was deposited (the evaporation rate was 0.1 A / s for the first 3 nm, and then the rate increased uniformly to 1 A / s), followed by the deposition of BCP with a wavelength of 15 nm (the evaporation rate was 0.1 A / s for the first 3 nm, and then the rate increased uniformly to 1 A / s).

[0073] 5) Fabrication of metal electrodes: On the electron transport layer at a vacuum level of 10... -7 During the Torr process, first deposit 3 nm of Cr, then deposit 80 nm of Cu (Au can be used as a substitute).

[0074] The absorption spectrum of the perovskite layer in this embodiment is shown below. Figure 8 Absorption stops at 780nm, with no infrared response.

[0075] The responsivity comparison chart of the perovskite photodetector and the commercially available high-performance silicon-based visible light detector (Hamamatsu S1087, Japan) under self-driven operation in this embodiment is shown below. Figure 9 Perovskite devices have higher responsivity than silicon detectors across the entire visible light spectrum, and their EQE efficiency at each wavelength is closer to the ideal efficiency of 100%.

[0076] Or prepare according to the following steps ( Figure 2 -b):

[0077] 1) Fabrication of transparent electrodes: A clean indium tin oxide-polyethylene terephthalate flexible substrate is subjected to surface oxygen plasma treatment;

[0078] 2) Preparation of the second charge transport layer: The second charge transport layer is spin-coated on the treated substrate at a speed of 3000-5000 rpm for 30-60 seconds, followed by annealing at 100-150℃ for 20-60 minutes.

[0079] 3) Preparation of the perovskite layer: A perovskite precursor solution is spin-coated onto the second charge transport layer, wherein the perovskite precursor solution is prepared by dissolving a mixture of metal cations, halogen or pseudohalogen anions and monovalent organic cations in a solvent, with the mass concentration of the solute in the solution being 15-50%; the solvent is any one or more combinations of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone.

[0080] 4) Preparation of the first charge transport layer: Spin-coat the first charge transport layer solution onto the perovskite layer at a speed of 3000-5000 rpm for 30-60 seconds;

[0081] 5) Fabrication of metal electrodes: Metal is deposited on the first charge transport layer by vapor deposition.

[0082] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A perovskite photodetector array with a curved focal plane, characterized in that: The flexible support substrate (1) and the shaped focal plane array (2) are included. The flexible support substrate (1) is made of a transparent flexible material and its curved shape is consistent with that of the shaped focal plane array (2). The shaped focal plane array (2) includes multiple perovskite photodetectors. The perovskite photodetectors include a light-absorbing layer and a charge transport layer. The light-absorbing layer and the charge transport layer are prepared layer by layer on the surface of the flexible support substrate (1) by spin coating or evaporation process. The light-absorbing layer is made of perovskite material. The curved shape of the flexible support substrate (1) is consistent with that of the shaped focal plane array (2).

2. The perovskite photodetector array according to claim 1, characterized in that, The perovskite photodetector comprises electrodes, a first charge transport layer, a second charge transport layer, and a perovskite layer; wherein the perovskite layer is a thin film formed of low-dimensional or three-dimensional perovskite, and the low-dimensional perovskite is any one or more combinations of zero-dimensional, one-dimensional, and two-dimensional; the first charge transport layer is one or more combinations of hole transport layer and electron blocking layer, and the second charge transport layer is one or more combinations of electron transport layer and hole blocking layer; or the first charge transport layer is one or more combinations of electron transport layer and hole blocking layer, and the second charge transport layer is one or more combinations of electron transport layer and hole blocking layer.

3. The perovskite photodetector array according to claim 1, characterized in that, The first and second charge transport layers are made from one or more of the following raw materials: poly(3,4-ethylenedioxythiophene / polystyrene sulfonate), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid, [2-(9H-carbazole-9-yl)ethyl]phosphonic acid, 2,2',7,7'-tetra[N,N-di(4-methoxyphenyl)amino]-9,9'-spirodifluorene, tin oxide, titanium oxide, C60 derivatives, C70 derivatives, C60, copper bath, and doped 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone.

4. The perovskite photodetector array according to claim 1, characterized in that, The perovskite layer is prepared by the following method: spin-coating a perovskite precursor solution onto a charge transport layer; the spin-coating speed is 1000-9000 rpm, and after spin-coating for 2-180 seconds, annealing is performed at 20-150°C for 1-150 minutes; wherein, the perovskite precursor solution is prepared by dissolving a mixture of metal cations, halogen or pseudohalogen anions and monovalent organic cations in a solvent, with the mass concentration of the solute in the solution being 15-45%; the solvent is any one or more combinations of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone.

5. The perovskite photodetector array according to claim 1, characterized in that, The metal cation is one or more of lead, rubidium, cesium, potassium, and sodium; the halogen or pseudohalogen anion includes one or more of fluorine, chlorine, bromine, iodine, and thiocyanate; and the monovalent organic cation includes one or more of methylamine, formamidinium, fluoroanisidine, fluorophenylethylamine, chloroanisidine, chlorophenylethylamine, bromoanisidine, and bromophenylethylamine.

6. The perovskite photodetector array according to claim 1, characterized in that, The perovskite photodetector, from top to bottom, consists of a transparent electrode, a first charge transport layer, a perovskite layer, a second charge transport layer, and a metal electrode, or from top to bottom, a transparent electrode, a second charge transport layer, a perovskite layer, a first charge transport layer, and a metal electrode.

7. The perovskite photodetector array according to claim 1, characterized in that, The transparent electrode is a flexible indium tin oxide-polyethylene terephthalate; the metal electrode is any one or a combination of gold, copper, chromium, silver, aluminum, and lithium fluoride.

8. A method for fabricating a perovskite photodetector array as described in any one of claims 1-7, characterized in that, Includes the following steps: 1) Fix a thin, flexible support substrate onto a transparent, rigid substrate; 2) A perovskite photodetector is obtained by spin-coating a hole transport layer, a perovskite active layer, and an electron transport layer on a flexible support substrate and then evaporating electrodes. Finally, a perovskite detector array with mechanical flexibility is obtained by removing the transparent rigid substrate. 3) The perovskite detector array is placed on a flexible support substrate (1) with a certain curvature, and shaped. After shaping, the shape is promoted by glue, and finally the shaped flexible perovskite photodetector array is obtained.

9. The method according to claim 8, characterized in that, Specifically, the following steps are included: 1) Fabrication of transparent electrodes: A clean indium tin oxide-polyethylene terephthalate flexible substrate is subjected to surface oxygen plasma treatment; 2) Preparation of the first charge transport layer: Spin-coat the first charge transport layer solution onto the treated substrate at a speed of 3000-6000 rpm for 30-60 seconds, and then anneal at 100-150℃ for 10-30 minutes. 3) Preparation of the perovskite layer: A perovskite precursor solution is spin-coated onto the first charge transport layer, wherein the perovskite precursor solution is prepared by dissolving a mixture of metal cations, halogen or pseudohalogen anions and monovalent organic cations in a solvent, with the mass concentration of the solute in the solution being 15-50%; the solvent is any one or a combination of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone. 4) Preparation of the second charge transport layer: spin-coating or vapor-depositing the second charge transport layer onto the perovskite layer; 5) Fabrication of metal electrodes: Metal is deposited on the second charge transport layer by vapor deposition. Or it may include the following steps: 1) Fabrication of transparent electrodes: A clean indium tin oxide-polyethylene terephthalate flexible substrate is subjected to surface oxygen plasma treatment; 2) Preparation of the second charge transport layer: The second charge transport layer is spin-coated on the treated substrate at a speed of 3000-5000 rpm for 30-60 seconds, followed by annealing at 100-150℃ for 20-60 minutes. 3) Preparation of the perovskite layer: A perovskite precursor solution is spin-coated onto the second charge transport layer, wherein the perovskite precursor solution is prepared by dissolving a mixture of metal cations, halogen or pseudohalogen anions and monovalent organic cations in a solvent, with the mass concentration of the solute in the solution being 15-50%; the solvent is any one or more combinations of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone. 4) Preparation of the first charge transport layer: Spin-coat the first charge transport layer solution onto the perovskite layer at a speed of 3000-5000 rpm for 30-60 seconds; 5) Fabrication of metal electrodes: Metal is deposited on the first charge transport layer by vapor deposition.

10. The application of the perovskite photodetector array with a curved focal plane as described in any one of claims 1-7, characterized in that, The applications include, but are not limited to, applications in medical endoscopes, applications in large astronomical telescopes, and applications in curved surface sensors in automotive surround view systems and autonomous driving assistance systems.

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