Self-driven low-dimensional non-lead perovskite ultraviolet detector and preparation method thereof

Abstract

The application belongs to the technical field of photoelectric detection, and relates to a self-driven low-dimensional non-lead perovskite ultraviolet detector. The device is based on an oxide semiconductor / low-dimensional perovskite type II heterojunction, and comprises a substrate, a patterned bottom electrode, an oxide semiconductor layer, a low-dimensional perovskite layer and a window top electrode. The patterned bottom electrode and the window top electrode are complementary in pattern and are both composite electrodes, and contain diffusion barrier layers respectively contacting the lower surface and the upper surface of the heterojunction. The window region is the light receiving region of the detector. The device has the advantages that the built-in electric field in the heterojunction is beneficial to the separation of photo-generated charges, and ultraviolet light can directly enter the light absorber, thereby avoiding transmission loss. The device adopts reverse and positive solvent vapor assisted gradient annealing technology to obtain a high-quality perovskite film. The diffusion barrier layers are used to simultaneously block the diffusion of ions at the bottom electrode / oxide and perovskite / top electrode interfaces. The application has the advantages of simple process, fast, stable and environmentally-friendly light response of the device.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of photoelectric detectors, in particular to a self-driven low-dimensional non-lead perovskite ultraviolet detector and a preparation method thereof. BACKGROUND

[0002] In recent years, in order to meet the needs of low power consumption of optoelectronic devices, self-driven photoelectric detectors have been widely studied because they do not require an external power supply. And using heterojunctions, Schottky junctions, etc., combined with vertical device structures is the main method to realize self-driven photoelectric detection without external pressure. However, the commonly used vertical structure inevitably involves a transparent conductive electrode layer, and the measured light will produce transmission loss in the transparent electrode layer before entering the light absorber. Although the light transmission loss is very small in the visible-infrared region, it has a very serious impact on ultraviolet. ITO (indium tin oxide), FTO (fluorine-doped tin oxide), etc. will greatly absorb short-wavelength (<~320nm) ultraviolet light, making it difficult to achieve self-driven ultraviolet detection, especially self-driven visible-blind ultraviolet detection. In addition, in the lateral device based on heterojunction, in order to realize self-driven, the same side electron and hole collecting electrodes are generally only in contact with the two ends of the junction, which generally requires patterning or micro-nano structuring of the light absorber. The current implementation of these methods is complex and is not conducive to the application of large-area integrated photosensitive chips.

[0003] In terms of materials, there are currently two main schemes for ultraviolet detectors; one is based on traditional narrow-bandgap materials such as crystalline silicon, which requires additional filtering to select ultraviolet absorption. The other uses wide-bandgap materials such as silicon carbide and gallium nitride, which have high ultraviolet / visible light rejection ratios. However, the material preparation cost is high, involves vacuum equipment, and is difficult to be flexible. Among wide-bandgap materials, wide-bandgap lead-based perovskites have good light absorption, can be prepared by solution method, and have fast device light response, but the stability of commonly used lead-based perovskites and the toxicity of lead elements are not conducive to practical application.

[0004] Therefore, it is a problem to be solved for application to prepare a self-driven detector with high sensitivity, low preparation cost, stability, environmental protection, and conducive to ultraviolet detection. SUMMARY

[0005] In view of the above problems existing in the prior art, the present application provides a self-driven low-dimensional non-lead perovskite ultraviolet detector and a preparation method thereof. The present application is realized by the following technical scheme:

[0006] In one aspect, the present application provides a self-driven low-dimensional non-lead perovskite ultraviolet detector, which comprises, from bottom to top, a substrate, a patterned bottom electrode, an oxide semiconductor layer, a low-dimensional perovskite layer, and a window top electrode.

[0007] The oxide semiconductor layer and the low-dimensional perovskite-like layer are opposite in conductive type, have similar band gaps, and can form a type II heterojunction; the patterned bottom electrode and the patterned top electrode are complementary in pattern, the patterned bottom electrode includes a window region, and the patterned bottom electrode and the window region of the patterned bottom electrode are completely overlapped in vertical projection;

[0008] The patterned bottom electrode and the patterned top electrode are composite electrodes, both of which contain diffusion barrier layers, and the diffusion barrier layers of the patterned bottom electrode and the patterned top electrode are in contact with the lower surface and the upper surface of the type II heterojunction, respectively; the window region is a light-receiving region of the ultraviolet detector, and ultraviolet light can directly enter the type II heterojunction from the window region.

[0009] As a preferred, the low-dimensional perovskite-like material in the low-dimensional perovskite-like layer is selected from a Cs-Ag-I system or a Cs-Cu-I system, the Cs-Ag-I system includes CsAg2I3 and Cs3Ag2I5, and the Cs-Cu-I system includes CsCu2I3 and Cs3Cu2I5.

[0010] As a preferred, the material of the oxide semiconductor layer is SnO2, ZnO, Ga2O3 or P-type NiO x , Cu2O.

[0011] As a preferred, the thickness of the oxide semiconductor layer is 50-200 nm, and the thickness of the low-dimensional perovskite-like layer is 100-400 nm.

[0012] As a preferred, the diffusion barrier layer has an ion diffusion blocking conductive material, including titanium nitride, titanium or tantalum, and the thickness is 1-10 nm.

[0013] Another aspect of the present application provides a preparation method of a self-driven low-dimensional non-lead perovskite ultraviolet detector, for preparing the self-driven low-dimensional non-lead perovskite ultraviolet detector described in any one of the above embodiments, and the preparation steps include:

[0014] S1: selecting a substrate and preparing a patterned bottom electrode on the substrate;

[0015] S2: using an oxygen vacancy compensation technology of hydrogen peroxide pyrolysis to prepare an oxide semiconductor layer on the surface of the substrate covered with the patterned bottom electrode;

[0016] S3: using a reverse and positive solvent vapor assisted gradient annealing technology to prepare a low-dimensional perovskite layer on the oxide semiconductor layer to form a type II heterojunction;

[0017] S4: preparing a window top electrode on the low-dimensional perovskite layer.

[0018] As preferred, in step S2, the preparation of the oxide semiconductor layer specifically comprises:

[0019] The oxide precursor solution is configured and 1%-8% hydrogen peroxide is added, wherein the oxide precursor solution comprises an oxide nanoparticle dispersion or a metal salt solution that can be pyrolyzed to generate an oxide, and the concentration is 1%-10%; the oxide semiconductor layer is prepared on the surface of the substrate wafer covered with the patterned bottom electrode through a spin coating, annealing (100-150 DEG C) process.

[0020] As preferred, in step S3, the preparation of the low-dimensional perovskite-like layer specifically comprises:

[0021] The perovskite-like precursor solution is configured and spin coated on the oxide semiconductor layer;

[0022] The thin film after spin coating is annealed at a first temperature in an anti-solvent vapor environment to obtain a thin film after first annealing;

[0023] The thin film after first annealing is annealed at a second temperature in a positive solvent vapor environment to obtain a thin film after second annealing, wherein the second temperature is greater than the first temperature, the first temperature is 50-90 DEG C, and the second temperature is 100-200 DEG C.

[0024] As preferred, the anti-solvent has the properties of easy evaporation and difficult solubility of perovskite and its precursor, and includes methanol and isopropyl alcohol; the positive solvent is a perovskite-soluble solvent, and includes tetrahydrofuran, N,N-dimethylformamide or dimethyl sulfoxide.

[0025] Compared with the prior art, the present application has the beneficial effects that:

[0026] 1) The self-driven ultraviolet detector provided by the present application has a carrier collection electrode on both sides of a light absorber (a heterojunction in the present application), and does not need to be patterned, and can fully utilize the built-in electric field of the heterojunction for longitudinal carrier separation, which helps to improve the light response rate; at the same time, compared with general longitudinal devices, the ultraviolet light can directly enter the light absorber in the device structure of the present application, avoiding the transmission loss of short-wavelength ultraviolet light through the transparent electrode in general longitudinal devices.

[0027] 2) The self-driven ultraviolet detector provided by the present application has a diffusion barrier layer in the composite electrode of the bottom and top electrodes, and the diffusion barrier layer directly contacts the upper and lower surfaces of the heterojunction, and blocks the diffusion of ions at the bottom electrode / oxide and perovskite-like material / top electrode interfaces, which is beneficial to the stability of the device.

[0028] 3) The self-driven ultraviolet detector provided by the application is prepared by using reverse and positive solvent vapor assisted gradient annealing technology to promote the formation of a transition state and regulate the crystallization process, and the quality of the perovskite film is improved by dissolution-recrystallization.

[0029] 4) The self-driven ultraviolet detector provided by the application is prepared by using reverse and positive solvent vapor assisted gradient annealing technology to promote the formation of a transition state and regulate the crystallization process, and the quality of the perovskite film is improved by dissolution-recrystallization.

[0030] The application will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 is a structural schematic diagram of a self-driven low-dimensional non-lead perovskite ultraviolet detector provided by an embodiment of the application;

[0032] Figure 2 is a flowchart of a preparation method of a self-driven low-dimensional non-lead perovskite ultraviolet detector provided by an embodiment of the application;

[0033] Figure 3 is a process schematic diagram of a preparation method of a self-driven low-dimensional non-lead perovskite ultraviolet detector provided by an embodiment of the application;

[0034] Figure 4 is an SEM diagram of a CsAg2I3 low-dimensional perovskite layer prepared by using the preparation method provided by an embodiment of the application;

[0035] Figure 5 is an XRD diagram of a CsAg2I3 low-dimensional perovskite layer prepared by using the preparation method provided by an embodiment of the application;

[0036] Figure 6 is a dark current diagram of a self-driven low-dimensional non-lead perovskite ultraviolet detector prepared by using the preparation method provided by an embodiment of the application;

[0037] Figure 7 is an I-V switch response diagram of a self-driven low-dimensional non-lead perovskite ultraviolet detector prepared by using the preparation method provided by an embodiment of the application;

[0038] Figure 8 is a diagram of the relationship between the light responsivity and the wavelength of a self-driven low-dimensional non-lead perovskite ultraviolet detector prepared by using the preparation method provided by an embodiment of the application. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of the application more clear, specific embodiments are described in detail with reference to the accompanying drawings.

[0040] Please refer toFigure 1 , Figure 1 is a structure diagram of a self-driven low-dimensional non-lead perovskite ultraviolet detector provided by the embodiment of the present application, which comprises, from bottom to top, a substrate 1, a patterned bottom electrode 2, an oxide semiconductor layer 3, a low-dimensional perovskite layer 4, and a window top electrode 5; wherein the conductive type of the oxide semiconductor layer 3 and the low-dimensional perovskite layer 4 is opposite, forming a type II heterojunction; the pattern of the bottom electrode 2 is complementary to the pattern of the window top electrode 5. Further, the pattern of the bottom electrode 2 is a closed figure, including a square or a circle, and completely coincides with the vertical projection of a window area 6. The window area 6 is the effective light receiving area of the ultraviolet detector. Ultraviolet light 7 can directly enter the heterojunction from the window area 6.

[0041] The low-dimensional non-lead perovskite material used in the embodiment is selected from a Cs-Ag-I system (including CsAg2I3 and Cs3Ag2I5) or a Cs-Cu-I system (including CsCu2I3 and Cs3Cu2I5). These materials have the advantages of high light absorption coefficient, solution preparation, etc. of commonly used lead-based perovskite materials, and meanwhile have the characteristics of stability, wide band gap and environmental protection, which are more conducive to ultraviolet detection. Different perovskite materials need to use oxide semiconductors with similar band gaps and opposite conductive types, which are conducive to further balancing and promoting the separation and transport of electrons and holes at the interface.

[0042] The material of the oxide semiconductor layer 3 in the embodiment needs to have a similar band gap and opposite conductive type to the selected low-dimensional perovskite material, and can be selected from N-type SnO2, ZnO, Ga2O3 or P-type NiO x or Cu2O. The thickness of the oxide semiconductor layer 3 is 50-200 nm, the thickness of the low-dimensional perovskite layer 4 is 100-400 nm, and the thickness of the bottom electrode 2 and the top electrode 5 is 80-150 nm.

[0043] Further, the patterned bottom electrode 2 and the window top electrode 5 are both metal composite electrodes containing a diffusion barrier layer attached to the heterojunction material. The bottom electrode is formed by first depositing a single metal electrode and then depositing a diffusion barrier layer to form a composite electrode; the top electrode is formed by first depositing a diffusion barrier layer and then depositing a single metal electrode to form a composite electrode. The diffusion barrier layer can be selected from titanium nitride, titanium and tantalum, and the diffusion barrier layer is used to block ion diffusion at the interface of the device.

[0044] The present application also provides a preparation method of a self-driven low-dimensional non-lead perovskite ultraviolet detector, please refer to Figure 2 and Figure 3 , which comprises the following steps:

[0045] S1: Select a substrate 1 and prepare a patterned bottom electrode 2 on the substrate 1.

[0046] A clean substrate wafer 1 is selected, and a patterned bottom electrode 2 is prepared on the substrate wafer 1 by combining a hollow mask with evaporation or a lift-off process. Specifically, a uniform photoresist is coated on the substrate wafer 1 by a spin coater and an annealing process, and the thickness of the photoresist is controlled by the spin coating speed. Then, the photoresist is patterned by exposure and development, and the patterned bottom electrode 2 is prepared by subsequent steps of electrode deposition, photoresist removal, and drying. The electrode deposition sequence is to first deposit a single-metal electrode and then deposit a diffusion barrier layer to form a composite electrode.

[0047] Optionally, the photoetching process uses ultraviolet photoetching, and the photoresist is selected from positive photoresist or negative photoresist. The thickness of the photoresist is 1-3 μm.

[0048] S2: An oxide semiconductor layer 3 is prepared on the surface of the substrate wafer with the patterned bottom electrode 2.

[0049] An oxide precursor solution is configured, and 1%-8% hydrogen peroxide is added to the solution. The oxide precursor solution includes an oxide nanoparticle dispersion or a solution of a metal salt that can be pyrolyzed to generate an oxide, such as tin chloride, gallium nitrate hydrate, etc. The concentration of the solution is 1%-10%. The oxide semiconductor layer 3 is prepared by a spin coating and annealing (100-150 °C) process. The hydrogen peroxide is used to reduce and inhibit oxygen vacancy defects in the oxide film.

[0050] S3: A perovskite-like layer 4 is prepared on the oxide semiconductor layer 3 to form a type II heterojunction.

[0051] A perovskite-like precursor solution is configured, such as a solution of CsI and AgI in a 1:2 molar ratio to synthesize CsAg2I3. The concentration of the solution is optionally 0.1-1 mol / L. Then, the perovskite-like precursor solution is spin coated on the oxide semiconductor layer 3. Subsequently, a reverse-solvent vapor assisted gradient annealing process and a positive-solvent vapor assisted gradient annealing process are performed to prepare the low-dimensional perovskite-like layer 4. Specifically, a reverse-solvent vapor is formed by adding a drop of the reverse-solvent on a hot stage and covering it with a lid. The sample of the spin-coated perovskite precursor solution is annealed in the reverse-solvent vapor environment at a first temperature (50-90 °C, i.e., the low temperature in the gradient annealing). Then, the thin film after the first annealing is annealed in a positive-solvent vapor environment at a second temperature (100-200 °C, i.e., the high temperature in the gradient annealing) to obtain a thin film after the second annealing. Compared with the conventional gradient annealing process, the reverse-solvent vapor assisted gradient annealing process and the positive-solvent vapor assisted gradient annealing process not only further accelerate the formation of the perovskite-like intermediate phase (the intermediate phase represents the state of forming a precursor complex with solvent coordination before crystallization) in the low-temperature annealing process, but also promote the dissolution-recrystallization process in the high-temperature annealing process, thereby optimizing the crystalline orientation and improving the perovskite film quality.

[0052] Optionally, the anti-solvent needs to have the characteristics of easy evaporation at room temperature, including methanol, isopropanol or ethanol; the normal solvent is a polar solvent, which can be tetrahydrofuran, N,N-dimethylformamide or dimethyl sulfoxide.

[0053] S4: preparing a window top electrode 5 on the low-dimensional perovskite layer 4.

[0054] The window top electrode 5 complementary to the pattern of the bottom electrode 2 is prepared by the same process of preparing the bottom electrode 2 in step 1. The electrode deposition sequence is different from that in step S1, that is, a diffusion barrier layer is first deposited and then a single-metal electrode is deposited to form a composite electrode. The effective contact area of the top electrode 5 is consistent with that of the bottom electrode 2 to balance the effective collection area of electrons and holes. The window area of the top electrode 5 is the light receiving area of the device.

[0055] Example 1

[0056] The embodiment provides a preparation method of a self-driven low-dimensional non-lead perovskite ultraviolet detector based on a heterojunction SnO2 / 1D-CsAg2I3, and the preparation method comprises the following steps:

[0057] S1: selecting a flat glass substrate, sequentially performing ultrasonic cleaning for 5 minutes in acetone, alcohol and deionized water, blowing dry with a nitrogen gun, then baking the clean substrate wafer 1 on a hot plate at 180 DEG C for 5 minutes, and performing oxygen plasma treatment for 3 minutes;

[0058] S2: preparing a square patterned bottom electrode on the clean substrate wafer 1 by means of evaporation combined with a hollowed-out hard mask process, the size is 3*3 mm, the material is 100 nm Au / 3 nm Ti (Au is evaporated first, and then Ti is evaporated), and the evaporation rate is controlled at 0.2 nm / s.

[0059] S3: configuring a 3% SnCl2 aqueous solution precursor, adding 1% to 8% hydrogen peroxide, preparing an oxide SnO2 semiconductor polycrystalline thin film through a solution spin coating-annealing process, the spin coating speed is 3000 rpm, the time is 30 s, the annealing temperature is 170 DEG C, and the time is 60 min, and an oxide semiconductor layer 3 is formed.

[0060] S4: configuring a 0.5 mol / L perovskite precursor solution, wherein the molar ratio of CsI and AgI is 1:2, the solution is dissolved in dimethyl sulfoxide, and a perovskite thin film is prepared through spin coating and anti-solvent (IPA) and normal solvent (THF) vapor assisted gradient annealing, wherein the spin coating rate is 500 rpm for 10 s and then 2000 rpm for 30 s. The anti-solvent vapor assisted low-temperature (50 DEG C) annealing time is 10 min, the normal solvent vapor assisted high-temperature (100 DEG C) annealing time is 60 min, and a low-dimensional perovskite layer 4 is formed.

[0061] S5: A window top electrode 5 complementary to the pattern of the bottom electrode 2 is prepared by using thermal evaporation combined with a hollow hard mask process. The size of the window area 6 is consistent with the pattern of the bottom electrode 2, and the outer size of the top electrode 5 is 4.3*4.3mm, so that the effective contact area of the electrode 5 is consistent with the bottom electrode. The electrode material is 5nm Ti / 100nm Au (Ti is evaporated first, and then Au is evaporated).

[0062] See Figure 4 to Figure 8 , Figure 4 is an SEM image of a CsAg2I3 low-dimensional perovskite layer prepared by the preparation method provided in the embodiments of the present application, and it can be seen that a smooth and flat film is obtained, Figure 5 is an XRD image of a CsAg2I3 low-dimensional perovskite layer prepared by the preparation method provided in the embodiments of the present application, and the strong XRD peak and the lower half-width indicate excellent crystallization, Figure 6 is a dark current image of a self-driven low-dimensional non-lead perovskite ultraviolet detector prepared by the preparation method provided in the embodiments of the present application, and it has the lowest dark current at 0V, so that the detector has a higher detection rate under no external voltage (0V). Figure 7 is a switching response I-V image of a self-driven low-dimensional non-lead perovskite ultraviolet detector prepared by the preparation method provided in the embodiments of the present application, and the light response time is 46 / 49μs. Figure 8 is a graph of the relationship between the light response and the wavelength of a self-driven low-dimensional non-lead perovskite ultraviolet detector prepared by the preparation method provided in the embodiments of the present application. It can be seen that the response can reach 0.11A / W under 300nm ultraviolet, and it has a high inhibition effect on visible light and infrared bands. And the detection rate can reach ~10 12 Jones.

[0063] Example Two

[0064] Based on example one, the present embodiment provides a preparation method of a self-driven low-dimensional non-lead perovskite ultraviolet detector based on a heterojunction Ga2O3 / 0D-Cs3Cu2I5, and the preparation method comprises:

[0065] S1: A flat glass substrate is selected, and is sequentially subjected to ultrasonic cleaning in acetone, alcohol and deionized water for 5 minutes, is blown dry by a nitrogen gun, and is then baked on a hot plate at 180℃ for 5 minutes to obtain a clean substrate, and is treated by oxygen plasma for 3min.

[0066] S2: A square bottom electrode pattern is prepared on the clean substrate by evaporation combined with a hollow hard mask process, and the electrode size is 3*3mm, and the material is 100nm Au / 3nm Ti (Au is evaporated first, and then Ti is evaporated), and the evaporation rate is controlled at 0.2nm / s.

[0067] S3: 2% precursor hydrated gallium nitrate / ethylene glycol methyl ether solution was configured, and 3% hydrogen peroxide was added, and a Ga2O3 semiconductor polycrystalline thin film was prepared by combining a spin-coating and annealing process, with a spin-coating speed of 6000 rpm and a time of 30 s, an annealing temperature of 500°C, and a time of 1.5 h.

[0068] S4: A 4% perovskite-like precursor solution was configured, with a CsI / CuI molar ratio of 3:2, dissolved in dimethyl sulfoxide solvent, and a perovskite thin film was prepared by spin coating and reverse solvent (IPA) and normal solvent (THF) vapor assisted gradient annealing, with a reverse solvent vapor assisted low temperature (70°C) annealing time of 10 min and a normal solvent vapor assisted high temperature (160°C) annealing time of 60 min, to form Cs3Cu2I5.

[0069] S5: A top electrode window pattern complementary to the bottom electrode was prepared by using thermal evaporation combined with a hollow hard mask process. The size of the area within the window was consistent with the bottom electrode, and the outer size was 4.3*4.3 mm, with an electrode of 5 nm Ti / 100 nm Au (Ti was evaporated first, and then Au was evaporated).

[0070] The above is a further detailed description of the present application in combination with specific preferred embodiments, and the specific implementation of the present application should not be limited to these descriptions. Modifications made by those of ordinary skill in the art without departing from the concept of the present application should be considered within the scope of protection of the present application.

Claims

1. A self-driven low-dimensional non-lead perovskite ultraviolet detector, characterized in that, From bottom to top, the substrate wafer, the patterned bottom electrode, the oxide semiconductor layer, the low-dimensional perovskite-like layer and the window top electrode are sequentially included; The material of the oxide semiconductor layer and the low-dimensional perovskite-like layer is a wide band gap material with similar band gap and opposite conductivity type, and can form a type II heterojunction; the pattern of the patterned bottom electrode and the window top electrode is complementary, and the vertical projection of the window area of the patterned bottom electrode and the window top electrode is completely overlapped; The patterned bottom electrode is a single metal layer / diffusion barrier layer composite electrode, wherein the diffusion barrier layer is in contact with the oxide semiconductor layer; the window top electrode is a diffusion barrier layer / single metal layer composite electrode, wherein the diffusion barrier layer is in contact with the low-dimensional perovskite-like layer; the window area is the light receiving area of the ultraviolet detector, and the ultraviolet light can directly enter the type II heterojunction from the window area; The low-dimensional perovskite-like material in the low-dimensional perovskite-like layer is selected from Cs-Ag-I system or Cs-Cu-I system, the Cs-Ag-I system includes CsAg2I3 and Cs3Ag2I5, and the Cs-Cu-I system includes CsCu2I3 and Cs3Cu2I5; The material of the oxide semiconductor layer is Sn02, ZnO, Ga203, NiO x or Cu20. The thickness of the oxide semiconductor layer is 50-200 nm, and the thickness of the low-dimensional perovskite-like layer is 100-400 nm; The diffusion barrier layer has an ion diffusion blocking conductive material, including titanium nitride, titanium or tantalum, and the thickness is 1-10 nm.

2. A method for preparing a self-driven low-dimensional non-lead perovskite ultraviolet detector, characterized in that, A self-driven low-dimensional non-lead perovskite ultraviolet detector is prepared by the following method: S1: selecting a substrate wafer and preparing a patterned bottom electrode on the substrate wafer; S2: using the oxygen vacancy compensation technology of hydrogen peroxide hydrolysis to prepare an oxide semiconductor layer on the surface of the substrate wafer covered with the patterned bottom electrode; S3: using the reverse and positive solvent vapor assisted gradient annealing technology to prepare a low-dimensional perovskite-like layer on the oxide semiconductor layer to form a type II heterojunction; S4: preparing a window top electrode on the low-dimensional perovskite-like layer.

3. The method for preparing the self-driven low-dimensional non-lead perovskite ultraviolet detector according to claim 2, characterized in that: Using the oxygen vacancy compensation technology of hydrogen peroxide hydrolysis to prepare an oxide semiconductor layer on the surface of the substrate wafer covered with the patterned bottom electrode, comprising: Configuring an oxide precursor solution and adding hydrogen peroxide with a concentration of 1%-8%, wherein the oxide precursor solution includes an oxide nanoparticle dispersion or a metal salt solution that can be pyrolyzed to generate an oxide with a concentration of 1%-10%; preparing the oxide semiconductor layer on the surface of the substrate wafer covered with the patterned bottom electrode by spin coating and annealing process, wherein the annealing temperature is 100-150℃.

4. The method for preparing a self-driven low-dimensional non-lead perovskite ultraviolet detector according to claim 2, characterized in that: Using the reverse and positive solvent vapor assisted gradient annealing technology to prepare a low-dimensional perovskite-like layer on the oxide semiconductor layer to form a type II heterojunction, comprising: Configuring a perovskite-like precursor solution and spin coating on the oxide semiconductor layer; In the reverse solvent vapor environment, annealing the spin-coated film at a first temperature to obtain a first annealed film; In the positive solvent vapor environment, annealing the first annealed film at a second temperature to obtain a second annealed film. In a positive solvent vapor environment, the thin film after the first annealing is annealed at a second temperature to obtain a second annealed thin film, wherein the second temperature is greater than the first temperature, the first temperature is 50-90 ℃, and the second temperature is 100-200 ℃.

5. The method for preparing a self-driven low-dimensional non-lead perovskite ultraviolet detector according to claim 4, characterized in that: The anti-solvent has volatile properties and is difficult to dissolve the perovskite and its precursors, including methanol and isopropyl alcohol, and the positive solvent is a perovskite-soluble solvent, including tetrahydrofuran, N,N-dimethylformamide or dimethyl sulfoxide.

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