Diode type photoelectric sensor and method of manufacturing the same

Abstract

This invention provides a diode-type photoelectric sensor, comprising a substrate, a perovskite thin film layer, an organic semiconductor layer, and electrodes. The perovskite thin film layer is disposed on a portion of the upper surface of the substrate, and is prepared by chemical vapor deposition. The perovskite thin film layer comprises lead halide and cesium halide in a molar ratio of 1:1. A portion of the organic semiconductor layer is disposed on the upper surface of the substrate, and the remaining portion is disposed on the upper surface of the perovskite thin film layer. The electrodes include a positive electrode and a negative electrode. This invention solves the problems of existing diode-type photoelectric sensors, such as complex fabrication processes, easy leakage, large dark current, and the inability to obtain color information of light, which can only detect light intensity. This invention also provides a method for fabricating a diode-type photoelectric sensor.

Description

Technical Field

[0001] This invention relates to the field of photoelectric sensor technology, and in particular to a diode-type photoelectric sensor and its fabrication method. Background Technology

[0002] As devices that convert light signals into electrical signals, photoelectric sensors play a crucial role in human-computer interaction, information transmission, and data acquisition applications in the intelligent era. Active layer materials that can be used in photoelectric sensors include inorganic semiconductors, organic semiconductors, and organic-inorganic hybrid semiconductors. However, limited by their working principle, current photoelectric sensors can mostly only detect light intensity, but cannot obtain color information.

[0003] Chinese Patent Publication No. CN111987185 A discloses a double perovskite thin-film device with photodiode effect, its fabrication method, and its application. This invention involves spin-coating an LNO or LSMO oxide thin film onto a Si wafer using a sol-gel method, annealing it at 750–800°C to create a bottom electrode, then spin-coating a BFCO thin film onto the LNO film and annealing it at 750–800°C, and finally depositing a metal top electrode onto the BFCO film, forming a top electrode / BFCO thin film / bottom electrode / n-Si substrate structure. This invention prepares the double perovskite thin-film device with photodiode effect using a solution method. However, this solution-based fabrication method is difficult to pattern, requiring the fabrication of a stacked structure, which is prone to leakage current. Furthermore, the fabrication process is complex. Moreover, this double perovskite thin-film device with photodiode effect can only detect light intensity.

[0004] Therefore, it is necessary to develop a diode-type photoelectric sensor and its fabrication method to avoid the aforementioned problems existing in the prior art. Summary of the Invention

[0005] The purpose of this invention is to provide a diode-type photoelectric sensor and its fabrication method, which solves the problems of existing diode-type photoelectric sensors having complex fabrication processes, easy leakage, large dark current, and the inability to obtain light color information, which can only detect light intensity.

[0006] To achieve the above objectives, a diode-type photoelectric sensor includes: a substrate, a perovskite thin film layer, an organic semiconductor layer, and electrodes; the perovskite thin film layer is disposed on a portion of the upper surface of the substrate, and is prepared by chemical vapor deposition; the material of the perovskite thin film layer includes lead halide and cesium halide, with a molar ratio of 1:1; the lead halide is selected from any one of lead chloride, lead bromide, and lead iodide, and the cesium halide is selected from any one of cesium chloride, cesium bromide, and cesium iodide; a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the substrate, and the remaining portion of the organic semiconductor layer is disposed on a portion of the upper surface of the perovskite thin film layer; the electrodes include a positive electrode and a negative electrode.

[0007] The advantages of the diode-type photoelectric sensor of the present invention are as follows: The perovskite thin film layer is prepared by chemical vapor deposition, which reduces the fabrication process of diode-type photoelectric sensors in the prior art and solves the problem of leakage current in the stacked structure of diode-type photoelectric sensors in the prior art; the materials of the perovskite thin film layer include lead halide and cesium halide, and the molar ratio of lead halide to cesium halide is 1:1, so that the formed perovskite thin film layer is a cubic phase perovskite thin film layer composed of cesium, lead, and halogen elements in a ratio of 1:1:3. This cubic phase perovskite thin film layer has a dense structure, and the resulting perovskite thin film layer has good morphology, uniformity, and stability, which can improve the photoelectric performance of the diode-type photoelectric sensor; moreover, the lead halide is selected from any one of lead chloride, lead bromide, and lead iodide, and the cesium halide is selected from any one of cesium chloride, cesium bromide, and cesium iodide, so that the perovskite thin film layer can be finely controlled. - ,Br - Cl - The invention achieves the detection of light intensity and color by adjusting the ratio of three halide ions. It solves the problems of existing diode-type photoelectric sensors, which have complex manufacturing processes, are prone to leakage, have large dark currents, and can only detect light intensity but cannot obtain light color information.

[0008] Preferably, the positive electrode is disposed on the upper surface of the perovskite thin film layer, and the negative electrode is disposed on the upper surface of the organic semiconductor layer. The beneficial effect is that a unidirectional diode-type photoelectric sensor is obtained, which has good rectification characteristics, fast response speed, stable operation, and excellent light detection capability.

[0009] Preferably, the perovskite thin film layer includes a first perovskite thin film layer and a second perovskite thin film layer, and the first perovskite thin film layer and the second perovskite thin film layer are separated by a portion of the organic semiconductor layer and disposed on a portion of the upper surface of the substrate. The positive electrode is disposed on either the upper surface of the first perovskite thin film layer or the upper surface of the second perovskite thin film layer, and the negative electrode is disposed on the other of the upper surface of the first perovskite thin film layer and the upper surface of the second perovskite thin film layer. Its advantages are: it yields a bidirectional diode-type photoelectric sensor, which responds differently to different light wavelengths under different voltages, exhibits excellent color imaging capabilities, and can effectively reduce dark current and improve photoelectric detection performance.

[0010] Preferably, the thickness of both the perovskite thin film layer and the organic semiconductor layer is 50 nm to 1 μm. The advantage of this is that limiting the thickness of the perovskite thin film layer and the organic semiconductor layer to 50 nm to 1 μm ensures that the resulting diode-type photoelectric sensor does not leak current.

[0011] Preferably, the thickness of the first perovskite film layer is the same as the thickness of the second perovskite film layer, and the spacing between the first and second perovskite film layers is 100 μm to 200 μm. The advantages are: when the thickness of the first and second perovskite film layers is the same, the resulting first and second perovskite film layers have the same photoelectric properties and photoresponse, enabling better detection of light intensity and color; if the spacing between the first and second perovskite film layers is too small, halogen atoms in both layers will diffuse, causing them to merge into a single perovskite film layer.

[0012] Preferably, the first perovskite thin film layer and the second perovskite thin film layer are symmetrically arranged about the central axis of the substrate. This has the intended effect of ensuring that the light absorption efficiency and photoresponse of the first and second perovskite thin film layers are identical.

[0013] Preferably, the organic semiconductor layer is made of either C8-BTBT or DNTT. The advantage is that both C8-BTBT and DNTT are wide-bandgap organic semiconductors, which can better integrate with perovskite thin films, resulting in improved performance of the resulting diode-type photoelectric sensor.

[0014] Preferably, the substrate is a flexible substrate, and the material of the flexible substrate is either PI or PET. The advantage is that since both PI and PET are flexible substrates, the photocurrent of the resulting diode-type photoelectric sensor remains essentially unchanged after different bending angles and bending cycles.

[0015] Preferably, the materials of the positive electrode and the negative electrode are conductive materials, including any one of gold, nickel, platinum, tungsten, and silver. The advantage is that the conductive material selected from any one of gold, nickel, platinum, tungsten, and silver can form an ohmic contact with the organic semiconductor layer or the perovskite thin film layer in contact with the conductive material.

[0016] Another objective of this invention is to provide a method for fabricating a diode-type photoelectric sensor, comprising the following steps: S1: providing a substrate; S2: forming a perovskite thin film layer on a portion of the upper surface of the substrate using a chemical vapor deposition method, then forming an organic semiconductor layer, a positive electrode, and a negative electrode, wherein a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the substrate, and the remaining portion of the organic semiconductor layer is disposed on a portion of the upper surface of the perovskite thin film layer; and wherein the material of the perovskite thin film layer includes lead halide and cesium halide, wherein the molar ratio of lead halide to cesium halide is 1:1, wherein the lead halide is selected from any one of lead chloride, lead bromide, and lead iodide, and wherein the cesium halide is selected from any one of cesium chloride, cesium bromide, and cesium iodide.

[0017] The beneficial effects of the method for fabricating the diode-type photoelectric sensor of the present invention are as follows: The perovskite thin film layer is prepared by chemical vapor deposition, which reduces the fabrication process of diode-type photoelectric sensors in the prior art and solves the problem of leakage current in the stacked structure of diode-type photoelectric sensors in the prior art; the materials of the perovskite thin film layer include lead halide and cesium halide, and the molar ratio of lead halide to cesium halide is 1:1, so that the formed perovskite thin film layer is a cubic phase perovskite thin film layer composed of cesium, lead, and halogen elements in a ratio of 1:1:3. This cubic phase perovskite thin film layer has a dense structure, and the resulting perovskite thin film layer has good morphology, uniformity, and stability, which can improve the photoelectric performance of the diode-type photoelectric sensor; moreover, the lead halide is selected from any one of lead chloride, lead bromide, and lead iodide, and the cesium halide is selected from any one of cesium chloride, cesium bromide, and cesium iodide, so that the perovskite thin film layer can be finely controlled. - ,Br - Cl -The invention detects the intensity and color of light by measuring the ratio of three halide ions. This invention solves the problems of existing diode-type photoelectric sensors, which have complex manufacturing processes, are prone to leakage, have large dark currents, and can only detect the intensity of light but cannot obtain the color information of light.

[0018] Preferably, in step S2, after forming a perovskite thin film layer on the upper surface of the substrate using chemical vapor deposition, an organic semiconductor layer, a positive electrode, and a negative electrode are formed, with a portion of the organic semiconductor layer disposed on the upper surface of the substrate and the remaining portion of the organic semiconductor layer disposed on the upper surface of the perovskite thin film layer, the step includes: S201: depositing lead halide onto the upper surface of the substrate using chemical vapor deposition, then depositing cesium halide onto the upper surface of the lead halide, and finally performing thermal annealing to form the perovskite thin film layer on the upper surface of the substrate; S202: forming an organic semiconductor layer, with a portion of the organic semiconductor layer disposed on the upper surface of the substrate and the remaining portion of the organic semiconductor layer disposed on the upper surface of the perovskite thin film layer; S203: forming the positive electrode on the upper surface of the perovskite thin film layer and forming the negative electrode on the upper surface of the organic semiconductor layer. Its beneficial effects are as follows: the preparation method yields a unidirectional diode type photoelectric sensor, which has good rectification characteristics, fast response speed, stable operation, and excellent light detection capability.

[0019] Preferably, in step S2, after forming a perovskite thin film layer on the upper surface of the substrate using chemical vapor deposition, an organic semiconductor layer, a positive electrode, and a negative electrode are formed, and a portion of the organic semiconductor layer is disposed on the upper surface of the substrate, while the remaining portion of the organic semiconductor layer is disposed on the upper surface of the perovskite thin film layer, the step includes: S211: depositing lead halide onto the upper surface of the substrate using chemical vapor deposition, then depositing cesium halide onto the upper surface of the lead halide, and finally performing thermal annealing to form a first perovskite thin film layer and a second perovskite thin film layer on the upper surface of the substrate, and ensuring that the first perovskite thin film layer and the second perovskite thin film layer are disposed on the upper surface of the substrate. S212: An organic semiconductor layer is formed, with a portion of the organic semiconductor layer disposed on a portion of the upper surface of the first perovskite thin film layer and a portion of the upper surface of the second perovskite thin film layer, and the remaining portion of the organic semiconductor layer disposed on the upper surface of the substrate between the first and second perovskite thin film layers; S213: The positive electrode is disposed on either the upper surface of the first perovskite thin film layer or the upper surface of the second perovskite thin film layer, and the negative electrode is disposed on the other of the upper surface of the first and second perovskite thin film layers. Its beneficial effects are: this fabrication method yields a bidirectional diode-type photoelectric sensor, which responds differently to different light wavelengths under different voltages, exhibits excellent color imaging capabilities, and can effectively reduce dark current and improve photoelectric detection performance.

[0020] Preferably, the temperature of the heat annealing treatment is 100℃~150℃, and the time of the heat annealing treatment is 30min~60min. The beneficial effect is that the perovskite film obtained at the heat annealing temperature and within the heat annealing time has better uniformity and a better morphology. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of a unidirectional diode-type photoelectric sensor in an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the bidirectional diode-type photoelectric sensor in an embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of the bandgap fitting images of three perovskite films in the embodiments of the present invention;

[0024] Figure 4 This is a schematic diagram of the photoelectric characteristic curves of the CsPbBrCl2 perovskite thin-film diode type photoelectric sensor in an embodiment of the present invention.

[0025] Figure 5 This is a schematic diagram of the photocurrent of the CsPbBrCl2 perovskite thin-film photodiode device as a function of light intensity in an embodiment of the present invention.

[0026] Figure 6 This is a schematic diagram of the photoelectric characteristic curves of the CsPbBr3 perovskite thin-film diode type photoelectric sensor in an embodiment of the present invention.

[0027] Figure 7 This is a schematic diagram of the photocurrent of the CsPbBr3 perovskite thin-film diode photoelectric sensor as a function of light intensity in an embodiment of the present invention.

[0028] Figure 8 This is a schematic diagram of the photoelectric characteristic curves of the CsPbI2Br perovskite thin-film diode type photoelectric sensor in an embodiment of the present invention.

[0029] Figure 9 This is a schematic diagram of the photocurrent of the CsPbI2Br perovskite thin-film diode photoelectric sensor as a function of light intensity in an embodiment of the present invention.

[0030] Figure 10 This is a schematic diagram of the photoelectric characteristic curves of the CsPbBrCl2-CsPbBr3 perovskite thin film bidirectional diode-type photoelectric sensor in an embodiment of the present invention.

[0031] Figure 11 This is a schematic diagram of the photoelectric characteristic curves of the CsPbBr3-CsPbI2Br perovskite thin film bidirectional diode type photoelectric sensor in an embodiment of the present invention.

[0032] Figure 12 This is a schematic diagram of the change in photocurrent of a unidirectional flexible CsPbI2Br perovskite thin film diode photoelectric sensor with the number of bending cycles at a bending angle of 30°, as described in an embodiment of the present invention.

[0033] Figure 13 This is a schematic diagram illustrating the change of photocurrent over time in a unidirectional flexible CsPbI2Br perovskite thin-film diode photoelectric sensor after different bending angles, as shown in an embodiment of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, but does not exclude other elements or objects.

[0035] To overcome the problems existing in the prior art, the purpose of this invention is to provide a diode-type photoelectric sensor and its preparation method, which solves the problems that the diode-type photoelectric sensor has a complex preparation process, is prone to leakage, has a large dark current, and can only detect the intensity of light but cannot obtain the color information of light.

[0036] In some embodiments of the present invention, the diode-type photoelectric sensor includes: a substrate, a perovskite thin film layer, an organic semiconductor layer, and an electrode; the perovskite thin film layer is disposed on a portion of the upper surface of the substrate, the perovskite thin film layer is prepared by chemical vapor deposition, and the material of the perovskite thin film layer includes lead halide and cesium halide, the molar ratio of lead halide and cesium halide is 1:1, the lead halide is selected from any one of lead chloride, lead bromide, and lead iodide, and the cesium halide is selected from any one of cesium chloride, cesium bromide, and cesium iodide; a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the substrate, and the remaining portion of the organic semiconductor layer is disposed on a portion of the upper surface of the perovskite thin film layer; the electrode includes a positive electrode and a negative electrode. The perovskite thin film layer is prepared by chemical vapor deposition, which reduces the fabrication process of diode-type photoelectric sensors in existing technologies and solves the problem of leakage current in the stacked structure of diode-type photoelectric sensors. The materials of the perovskite thin film layer include lead halide and cesium halide, with a molar ratio of 1:1. This results in a cubic phase perovskite thin film layer composed of cesium, lead, and halogen elements in a ratio of 1:1:3. This cubic phase perovskite thin film layer has a dense structure, resulting in good morphology, uniformity, and stability, which can improve the photoelectric performance of the diode-type photoelectric sensor. Furthermore, the lead halide is selected from any one of lead chloride, lead bromide, and lead iodide, and the cesium halide is selected from any one of cesium chloride, cesium bromide, and cesium iodide, allowing for fine control of the Io. - ,Br - Cl- The invention detects the intensity and color of light by measuring the ratio of three halide ions. This invention solves the problems of existing diode-type photoelectric sensors, which have complex manufacturing processes, are prone to leakage, have large dark currents, and can only detect the intensity of light but cannot obtain the color information of light.

[0037] In some embodiments of the present invention, the positive electrode is disposed on the upper surface of the perovskite thin film layer, and the negative electrode is disposed on the upper surface of the organic semiconductor layer.

[0038] Figure 1 This is a schematic diagram of the structure of a unidirectional diode-type photoelectric sensor in an embodiment of the present invention.

[0039] In some embodiments of the present invention, reference is made to Figure 1 The diode-type photoelectric sensor includes a substrate 1, a perovskite thin film layer 2, an organic semiconductor layer 3, and electrodes (not shown in the figure). The perovskite thin film layer 2 is disposed on a portion of the upper surface of the substrate 1. The perovskite thin film layer 2 is prepared by chemical vapor deposition, and the material of the perovskite thin film layer 2 includes lead halide and cesium halide, with a molar ratio of 1:1. The lead halide is selected from any one of lead chloride, lead bromide, and lead iodide, and the cesium halide is selected from any one of cesium chloride, cesium bromide, and cesium iodide. A portion of the organic semiconductor layer 3 is disposed on a portion of the upper surface of the substrate 1, and the remaining portion of the organic semiconductor layer 3 is disposed on a portion of the upper surface of the perovskite thin film layer 2; the electrode includes a positive electrode 41 and a negative electrode 42; the positive electrode 41 is disposed on the upper surface of the perovskite thin film layer 2, and the negative electrode 42 is disposed on the upper surface of the organic semiconductor layer 3; this unidirectional diode-type photoelectric sensor (not shown in the figure) has good rectification characteristics, fast response speed, stable operation, and can effectively reduce dark current, and has excellent light detection capability.

[0040] In some embodiments of the present invention, the perovskite thin film layer includes a first perovskite thin film layer and a second perovskite thin film layer, wherein the first perovskite thin film layer and the second perovskite thin film layer are separated by a portion of the organic semiconductor layer and disposed on a portion of the upper surface of the substrate, the positive electrode is disposed on either the upper surface of the first perovskite thin film layer or the upper surface of the second perovskite thin film layer, and the negative electrode is disposed on the other of the upper surface of the first perovskite thin film layer and the upper surface of the second perovskite thin film layer.

[0041] In some specific embodiments of the present invention, the positive electrode is disposed on the upper surface of the first perovskite thin film layer, and the negative electrode is disposed on the upper surface of the second perovskite thin film layer.

[0042] In some other embodiments of the present invention, the positive electrode is disposed on the upper surface of the second perovskite thin film layer, and the negative electrode is disposed on the upper surface of the first perovskite thin film layer.

[0043] Figure 2 This is a schematic diagram of the structure of a bidirectional diode-type photoelectric sensor in an embodiment of the present invention.

[0044] In other embodiments of the present invention, reference is made to Figure 2 The diode-type photoelectric sensor includes a substrate 1, a first perovskite thin film layer 21, a second perovskite thin film layer 22, an organic semiconductor layer 3, and electrodes (not shown in the figure). The first perovskite thin film layer 21 and the second perovskite thin film layer 22 are disposed on a portion of the upper surface of the substrate 1. The first perovskite thin film layer 21 and the second perovskite thin film layer 22 are prepared by chemical vapor deposition. The materials of the first perovskite thin film layer 21 and the second perovskite thin film layer 22 include lead halide and cesium halide, with a molar ratio of 1:1. The lead halide is selected from any one of lead chloride, lead bromide, and lead iodide, and the cesium halide is selected from... The photoelectric sensor comprises any one of cesium chloride, cesium bromide, and cesium iodide; a portion of the organic semiconductor layer 3 is disposed on a portion of the upper surface of the substrate 1, and the remaining portion of the organic semiconductor layer 3 is disposed on a portion of the upper surface of the first perovskite thin film layer 21 and the second perovskite thin film layer 22; the electrode includes a positive electrode 41 and a negative electrode 42; the positive electrode 41 is disposed on the upper surface of the first perovskite thin film layer 21, and the negative electrode 42 is disposed on the upper surface of the second perovskite thin film layer 22; this bidirectional diode-type photoelectric sensor responds differently to different light wavelengths under different voltages, has excellent color imaging capabilities, and can effectively reduce dark current and improve photoelectric detection performance.

[0045] In some embodiments of the present invention, the thickness of the perovskite thin film layer and the thickness of the organic semiconductor layer are both 50 nm to 1 μm. By limiting the thickness of the perovskite thin film layer and the organic semiconductor layer to 50 nm to 1 μm, the resulting diode-type photoelectric sensor does not leak current.

[0046] In some specific embodiments of the present invention, the thickness of the perovskite thin film layer is any one of 50nm, 150nm, 300nm, 450nm, 600nm, 750nm, 900nm, and 1μm; the thickness of the organic semiconductor layer 3 is any one of 50nm, 150nm, 300nm, 450nm, 600nm, 750nm, 900nm, and 1μm.

[0047] Specifically, refer to Figure 1The thickness of the perovskite thin film layer 2 is 300 nm, the thickness of the organic semiconductor layer 3 is 300 nm, and the cross-sectional area of ​​the perovskite thin film layer 2 on the substrate 1 is equal to the cross-sectional area of ​​the organic semiconductor layer 3 on the substrate 1.

[0048] In some embodiments of the present invention, the thickness of the first perovskite thin film layer is the same as the thickness of the second perovskite thin film layer, and the spacing between the first perovskite thin film layer and the second perovskite thin film layer is 100 μm to 200 μm.

[0049] In other specific embodiments of the present invention, the thickness of the first perovskite thin film layer and the thickness of the second perovskite thin film layer are any one of 50nm, 150nm, 300nm, 450nm, 600nm, 750nm, 900nm, and 1μm, and the spacing between the first perovskite thin film layer and the second perovskite thin film layer is any one of 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, and 200μm.

[0050] Specifically, refer to Figure 2 The thickness of the first perovskite thin film layer 21 and the thickness of the second perovskite thin film layer 22 are both 300 nm, and the spacing between the first perovskite thin film layer 21 and the second perovskite thin film layer 22 is 150 μm.

[0051] In some embodiments of the present invention, reference is made to Figure 2 The first perovskite thin film layer 21 and the second perovskite thin film layer 22 are symmetrically arranged about the central axis of the substrate 1 to ensure that the light absorption efficiency and light response of the first perovskite thin film layer 21 and the second perovskite thin film layer 22 are the same.

[0052] Specifically, the central axis refers to the center line of an axially symmetrical figure, building, or other object, and all axially symmetrical objects will overlap when folded across this line.

[0053] In some embodiments of the present invention, the material of the organic semiconductor layer is either C8-BTBT or DNTT. Both C8-BTBT and DNTT are wide-bandgap organic semiconductors, which can better integrate with perovskite thin films, thereby improving the performance of the resulting diode-type photoelectric sensor.

[0054] Specifically, the C8-BTBT is 2,7-dioctyl[1]benzothiophene[3,2-B]benzothiophene; the DNTT is bisnaphtho[2,3-b:2',3'-f]thiophene[3,2-b]thiophene.

[0055] In some embodiments of the present invention, the substrate is a flexible substrate, and the material of the flexible substrate is either PI or PET. Both PI and PET are flexible substrates, and the photocurrent of the resulting diode-type photoelectric sensor remains basically unchanged after different bending angles and bending times.

[0056] Specifically, PI is polyimide; PET is polyethylene terephthalate.

[0057] In some specific embodiments of the present invention, the material of the organic semiconductor layer 3 is C8-BTBT, and the substrate is a flexible substrate, specifically, the flexible substrate is PI.

[0058] In some embodiments of the present invention, the materials of the positive electrode and the negative electrode are conductive materials, including any one of gold, nickel, platinum, tungsten and silver. The conductive material is selected from any one of gold, nickel, platinum, tungsten and silver, and the conductive material and the organic semiconductor layer or the perovskite thin film layer in contact with it can form an ohmic contact.

[0059] In some specific embodiments of the present invention, the materials of the positive electrode 41 and the negative electrode 42 are conductive materials, specifically, the conductive material is gold.

[0060] In an embodiment of the present invention, a method for fabricating a diode-type photoelectric sensor is provided, comprising the following steps:

[0061] S1: Provides the substrate;

[0062] S2: After forming a perovskite thin film layer on the upper surface of the substrate using chemical vapor deposition, an organic semiconductor layer, a positive electrode, and a negative electrode are formed, and a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the substrate, while the remaining portion of the organic semiconductor layer is disposed on a portion of the upper surface of the perovskite thin film layer.

[0063] Furthermore, the material of the perovskite thin film layer includes lead halide and cesium halide, the molar ratio of lead halide and cesium halide is 1:1, the lead halide is selected from any one of lead chloride, lead bromide and lead iodide, and the cesium halide is selected from any one of cesium chloride, cesium bromide and cesium iodide.

[0064] Specifically, the perovskite thin film layer is prepared using chemical vapor deposition, which reduces the fabrication process of existing diode-type photoelectric sensors and solves the problem of leakage current in the stacked structure of existing diode-type photoelectric sensors. The materials of the perovskite thin film layer include lead halide and cesium halide, with a molar ratio of 1:1. This results in a cubic phase perovskite thin film layer composed of cesium, lead, and halogen elements in a ratio of 1:1:3. This cubic phase perovskite thin film layer has a dense structure, resulting in good morphology, uniformity, and stability, which improves the photoelectric performance of the diode-type photoelectric sensor. Furthermore, the lead halide is selected from any one of lead chloride, lead bromide, and lead iodide, and the cesium halide is selected from any one of cesium chloride, cesium bromide, and cesium iodide, allowing for fine control of the Io. - ,Br - Cl - The invention detects the intensity and color of light by measuring the ratio of three halide ions. This invention solves the problems of existing diode-type photoelectric sensors, which have complex manufacturing processes, are prone to leakage, have large dark currents, and can only detect the intensity of light but cannot obtain the color information of light.

[0065] In some embodiments of the present invention, in step S2, after forming a perovskite thin film layer on the upper surface of the substrate portion using chemical vapor deposition, an organic semiconductor layer, a positive electrode, and a negative electrode are formed, and a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the substrate, and the remaining portion of the organic semiconductor layer is disposed on a portion of the upper surface of the perovskite thin film layer, the step includes:

[0066] S201: The lead halide is deposited onto a portion of the upper surface of the substrate using a vapor phase evaporation method, then the cesium halide is deposited onto the upper surface of the lead halide, and finally a thermal annealing process is performed to form the perovskite thin film layer on a portion of the upper surface of the substrate.

[0067] S202: Form an organic semiconductor layer, and place a portion of the organic semiconductor layer on a portion of the upper surface of the substrate, and place the remaining portion of the organic semiconductor layer on a portion of the upper surface of the perovskite thin film layer;

[0068] S203: The positive electrode is formed on the upper surface of the perovskite thin film layer, and the negative electrode is formed on the upper surface of the organic semiconductor layer.

[0069] Specifically, the fabrication method yields a unidirectional diode-type photoelectric sensor, which has good rectification characteristics, fast response speed, stable operation, and excellent light detection capability.

[0070] In some embodiments of the present invention, in step S2, after forming a perovskite thin film layer on the upper surface of the substrate portion using chemical vapor deposition, an organic semiconductor layer, a positive electrode, and a negative electrode are formed, and a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the substrate, and the remaining portion of the organic semiconductor layer is disposed on a portion of the upper surface of the perovskite thin film layer, the step includes:

[0071] S211: The lead halide is deposited onto a portion of the upper surface of the substrate using a vapor phase evaporation method, then the cesium halide is deposited onto the upper surface of the lead halide, and finally a thermal annealing process is performed to form a first perovskite thin film layer and a second perovskite thin film layer on a portion of the upper surface of the substrate, and the first perovskite thin film layer and the second perovskite thin film layer are separated on a portion of the upper surface of the substrate by a portion of the organic semiconductor layer;

[0072] S212: An organic semiconductor layer is formed, and a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the first perovskite thin film layer and a portion of the upper surface of the second perovskite thin film layer, and the remaining portion of the organic semiconductor layer is disposed on the upper surface of the substrate between the first perovskite thin film layer and the second perovskite thin film layer.

[0073] S213: The positive electrode is disposed on either the upper surface of the first perovskite thin film layer or the upper surface of the second perovskite thin film layer, and the negative electrode is disposed on the other of the upper surface of the first perovskite thin film layer and the upper surface of the second perovskite thin film layer.

[0074] Specifically, the fabrication method yields a bidirectional diode-type photoelectric sensor. This bidirectional diode-type photoelectric sensor responds differently to different light wavelengths under different voltages, exhibits excellent color imaging capabilities, and can effectively reduce dark current and improve photoelectric detection performance.

[0075] In some embodiments of the present invention, the temperature of the thermal annealing is 100°C to 150°C, and the time of the thermal annealing is 30 min to 60 min; at the temperature and time of the thermal annealing, the perovskite film obtained has good uniformity and good morphology.

[0076] In some specific embodiments of the present invention, step S1 involves providing a substrate, and the specific steps include:

[0077] The clean silicon wafer was ultrasonically cleaned in acetone, isopropanol and 5% sulfuric acid aqueous solution for 0.5 hours in sequence, then rinsed with deionized water and ethanol, and finally the surface was quickly dried with a high-pressure nitrogen gun.

[0078] The cleaned substrate was then transferred to a nitrogen-filled glove box and immersed in a 5 mM APTES toluene solution for 12 h. After that, the substrate was transferred to toluene and sonicated for 10 min, followed by rinsing with isopropanol to obtain an APTES monolayer treated substrate.

[0079] Finally, the above substrate was transferred to a 48% HBr aqueous solution and soaked for 2 hours to convert the terminal amino groups of APTES into ammonium groups, thereby preparing an HBr-APTES monolayer treated substrate.

[0080] Specifically, perovskite has a highly symmetrical cubic crystal structure. At the interface between the perovskite material and the substrate, there are a large number of defects, mainly incompletely coordinated lead ions and halide ion vacancies. The presence of these defects will cause structural distortion of the perovskite, resulting in perovskite films with poor morphology. The N atom of the terminal amino group of APTES can form hydrogen bonds with lead ions, which can reduce the above defects to a certain extent, thereby obtaining perovskite films with better morphology.

[0081] In some specific embodiments of the present invention, in step S201, PbrCl2 is deposited onto a portion of the upper surface of the substrate using a vapor phase evaporation method, then CsBr is deposited onto the upper surface of PbrCl2, and finally a thermal annealing treatment is performed to form the CsPbBrCl2 perovskite thin film layer on a portion of the upper surface of the substrate.

[0082] Specifically, the steps include:

[0083] The HBr-APTES monolayer-treated substrate was attached to the top of the thermal evaporation equipment cavity and rotated at 10 rpm under a pressure of 10. -5 Under the condition of Pa, a beam source furnace containing the precursor PbrCl2 is heated and deposited on a portion of the upper surface of the substrate at a speed of 0.1 nm / s.

[0084] Then at a pressure of 10 -5 Under the condition of Pa, the beam source furnace containing the precursor CsBr is heated so that it evaporates at the same rate and sinks to the top surface of PbCl2.

[0085] Finally, the film was thermally annealed in air at 150°C for 30 minutes to obtain a continuous and uniform CsPbBrCl2 perovskite film layer.

[0086] In some specific embodiments of the present invention, in step S202, an organic semiconductor layer is formed, and a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the substrate, while the remaining portion of the organic semiconductor layer is disposed on a portion of the upper surface of the CsPbBrCl2 perovskite thin film layer; in step S203, the positive electrode is formed on the upper surface of the CsPbBrCl2 perovskite thin film layer, and the negative electrode is formed on the upper surface of the organic semiconductor layer.

[0087] Specifically, the process includes the following steps: using a stainless steel mask, depositing a C8-BTBT and gold electrode with a thickness of 300 nm on a portion of the upper surface of the substrate and a portion of the upper surface of the CsPbBrCl2 perovskite thin film layer with a thickness of 300 nm, thereby fabricating a unidirectional CsPbBrCl2 perovskite thin film diode-type photoelectric sensor.

[0088] Figure 3 This is a schematic diagram of the bandgap fitting images of three perovskite films in the embodiments of the present invention; Figure 4 This is a schematic diagram of the photoelectric characteristic curves of the CsPbBrCl2 perovskite thin-film diode type photoelectric sensor in an embodiment of the present invention. Figure 5 This is a schematic diagram of the photocurrent of a CsPbBrCl2 perovskite thin-film photodiode device as a function of light intensity in an embodiment of the present invention.

[0089] In some specific embodiments of the present invention, reference is made to Figure 4 The unidirectional CsPbBrCl2 perovskite thin-film diode photosensor exhibits rectification characteristics in the absence of light. When the light wavelength is greater than 420 nm, the CsPbBrCl2 perovskite thin film layer is not reverse conductive, and the unidirectional CsPbBrCl2 perovskite thin-film diode photosensor still exhibits rectification characteristics. When the light wavelength is 420 nm, the CsPbBrCl2 perovskite thin film layer is reverse conductive, and the unidirectional CsPbBrCl2 perovskite thin-film diode photosensor exhibits a certain reverse voltage photoresponse. (Reference) Figure 5 The photocurrent increases with increasing light intensity; reference Figure 3 This wavelength-dependent light response behavior matches the bandgap of the fitted CsPbBrCl2 perovskite film; because this unidirectional CsPbBrCl2 perovskite film diode-type photoelectric sensor uses the CsPbBrCl2 perovskite film layer, blue light detection can be achieved without a filter.

[0090] In some other specific embodiments of the present invention, in step S201, PbBr2 is deposited onto a portion of the upper surface of the substrate using a vapor phase evaporation method, then CsBr is deposited onto the upper surface of PbBr2, and finally a thermal annealing treatment is performed to form the CsPbBr3 perovskite thin film layer on a portion of the upper surface of the substrate.

[0091] Specifically, the steps include:

[0092] The HBr-APTES monolayer-treated substrate was attached to the top of the thermal evaporation equipment cavity and rotated at 10 rpm under a pressure of 10. -5 Under the condition of Pa, a beam source furnace containing the precursor PbBr2 is heated and deposited on a portion of the upper surface of the substrate at a speed of 0.1 nm / s.

[0093] Then at a pressure of 10 -5 Under the condition of Pa, the beam source furnace containing the precursor CsBr is heated so that it evaporates at the same rate and sinks to the top surface of PbBr2.

[0094] Finally, the film was thermally annealed in air at 140°C for 35 min to obtain a continuous and uniform CsPbBr3 perovskite film layer.

[0095] In some other specific embodiments of the present invention, in step S202, an organic semiconductor layer is formed, and a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the substrate, while the remaining portion of the organic semiconductor layer is disposed on a portion of the upper surface of the CsPbBr3 perovskite thin film layer; in step S203, the positive electrode is formed on the upper surface of the CsPbBr3 perovskite thin film layer, and the negative electrode is formed on the upper surface of the organic semiconductor layer.

[0096] Specifically, the process includes the following steps: using a stainless steel mask, depositing a 500nm thick C8-BTBT and gold electrode on a portion of the upper surface of the substrate and a portion of the upper surface of the 400nm thick CsPbBr3 perovskite thin film layer, to fabricate a unidirectional CsPbBr3 perovskite thin film diode-type photoelectric sensor.

[0097] Figure 6 This is a schematic diagram of the photoelectric characteristic curves of the CsPbBr3 perovskite thin-film diode type photoelectric sensor in an embodiment of the present invention. Figure 7 This is a schematic diagram of the photocurrent of the CsPbBr3 perovskite thin-film diode photoelectric sensor as a function of light intensity in an embodiment of the present invention.

[0098] In some specific embodiments of the present invention, reference is made to Figure 6In the absence of light, the unidirectional CsPbBr3 perovskite thin-film diode photosensor exhibits rectification characteristics. When the light wavelength is greater than 500 nm, the CsPbBr3 perovskite thin film layer is not reverse-biased, and the unidirectional CsPbBr3 perovskite thin-film diode photosensor still exhibits rectification characteristics. When the light wavelength is less than or equal to 500 nm, the CsPbBr3 perovskite thin film layer conducts in the reverse direction, and the unidirectional CsPbBr3 perovskite thin-film diode photosensor exhibits a certain reverse voltage photoresponse. (Refer to...) Figure 7 The photocurrent increases with increasing light intensity; reference Figure 3 This wavelength-dependent photoresponse behavior matches the bandgap of the fitted CsPbBr3 perovskite thin film. Because this unidirectional CsPbBr3 perovskite thin film diode-type photosensitive sensor uses the aforementioned CsPbBr3 perovskite thin film layer, green light detection can be achieved without a filter.

[0099] In some specific embodiments of the present invention, in step S201, PbI2 is deposited onto a portion of the upper surface of the substrate using a vapor phase evaporation method, then CsBr is deposited onto the upper surface of PbI2, and finally a thermal annealing process is performed to form the CsPbI2Br perovskite thin film layer on the portion of the upper surface of the substrate.

[0100] Specifically, the steps include:

[0101] The HBr-APTES monolayer-treated substrate was attached to the top of the thermal evaporation equipment cavity and rotated at 10 rpm under a pressure of 10. -5 Under the condition of Pa, a beam source furnace containing the precursor PbI2 is heated and deposited on a portion of the upper surface of the substrate at a speed of 0.1 nm / s.

[0102] Then at a pressure of 10 -5 Under the condition of Pa, the beam source furnace containing the precursor CsBr is heated so that it evaporates at the same rate and sinks to the top surface of PbI2.

[0103] Finally, the film was thermally annealed in air at 120°C for 40 min to obtain a continuous and uniform CsPbI2Br perovskite film layer.

[0104] In some specific embodiments of the present invention, in step S202, an organic semiconductor layer is formed, and a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the substrate, while the remaining portion of the organic semiconductor layer is disposed on a portion of the upper surface of the CsPbI2Br perovskite thin film layer; in step S203, the positive electrode is formed on the upper surface of the CsPbI2Br perovskite thin film layer, and the negative electrode is formed on the upper surface of the organic semiconductor layer.

[0105] Specifically, the process includes the following steps: using a stainless steel mask, depositing a C8-BTBT and gold electrode with a thickness of 300 nm on a portion of the upper surface of the substrate and a portion of the upper surface of the CsPbI2Br perovskite thin film layer with a thickness of 300 nm, thereby fabricating a unidirectional CsPbI2Br perovskite thin film diode-type photoelectric sensor.

[0106] Figure 8 This is a schematic diagram of the photoelectric characteristic curves of the CsPbI2Br perovskite thin-film diode type photoelectric sensor in an embodiment of the present invention. Figure 9 This is a schematic diagram of the photocurrent of the CsPbI2Br perovskite thin-film diode photoelectric sensor as a function of light intensity in an embodiment of the present invention.

[0107] In some specific embodiments of the present invention, reference is made to Figure 8 The unidirectional CsPbI2Br perovskite thin-film diode photosensor exhibits rectification characteristics in the absence of light. When the light wavelength is greater than 620 nm, the CsPbI2Br perovskite thin film is not reverse-biased, and the unidirectional CsPbI2Br perovskite thin-film diode photosensor still exhibits rectification characteristics. When the light wavelength is less than or equal to 620 nm, the CsPbI2Br perovskite thin film is reverse-biased, and the unidirectional CsPbI2Br perovskite thin-film diode photosensor exhibits a certain reverse voltage photoresponse. (Refer to...) Figure 9 The photocurrent increases with increasing light intensity; reference Figure 3 This wavelength-dependent light response behavior matches the bandgap of the fitted CsPbI2Br perovskite film; because this unidirectional CsPbI2Br perovskite film diode-type photoelectric sensor uses the CsPbI2Br perovskite film layer, red light detection can be achieved without a filter.

[0108] In some specific embodiments of the present invention, in step S211, lead halide is deposited onto a portion of the upper surface of the substrate using a vapor phase evaporation method, then cesium halide is deposited onto the upper surface of the lead halide, and finally thermal annealing is performed to form a first perovskite thin film layer and a second perovskite thin film layer on a portion of the upper surface of the substrate, wherein the first perovskite thin film layer and the second perovskite thin film layer are separated on a portion of the upper surface of the substrate by a portion of the organic semiconductor layer.

[0109] Specifically, the steps include:

[0110] The HBr-APTES monolayer-treated substrate was attached to the top of the thermal evaporation equipment cavity and rotated at 10 rpm under a pressure of 10. -5 Under the condition of Pa, a beam source furnace containing the precursor PbrCl2 is heated and deposited on a portion of the upper surface of the substrate at a speed of 0.1 nm / s.

[0111] Then at a pressure of 10 -5 Under the condition of Pa, the beam source furnace containing the precursor CsBr is heated so that it evaporates at the same rate and sinks to the top surface of PbCl2.

[0112] The HBr-APTES monolayer-treated substrate was attached to the top of the thermal evaporation equipment cavity and rotated at 10 rpm under a pressure of 10. -5 Under the condition of Pa, a beam source furnace containing the precursor PbBr2 is heated and deposited on a portion of the upper surface of the substrate at a speed of 0.1 nm / s.

[0113] Then at a pressure of 10 -5 Under the condition of Pa, the beam source furnace containing the precursor CsBr is heated so that it evaporates at the same rate and sinks to the top surface of PbCl2.

[0114] Finally, the film was thermally annealed in air at 110°C for 50 min to obtain a continuous and uniform CsPbBrCl2-CsPbBr3 perovskite film layer.

[0115] In some specific embodiments of the present invention, in step S212, an organic semiconductor layer is formed, and a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the first perovskite thin film layer and a portion of the upper surface of the second perovskite thin film layer, and the remaining portion of the organic semiconductor layer is disposed on the upper surface of the substrate between the first perovskite thin film layer and the second perovskite thin film layer; in step S213, the positive electrode is disposed on either the upper surface of the first perovskite thin film layer or the upper surface of the second perovskite thin film layer, and the negative electrode is disposed on the other of the upper surface of the first perovskite thin film layer and the upper surface of the second perovskite thin film layer.

[0116] Specifically, the process includes the following steps: using a stainless steel mask, depositing a C8-BTBT layer with a thickness of 450 nm and a gold electrode on a portion of the upper surface of the substrate, a portion of the upper surface of the CsPbBrCl2 perovskite thin film layer with a thickness of 300 nm, and a portion of the upper surface of the CsPbBr3 perovskite thin film layer with a thickness of 300 nm, to fabricate a CsPbBrCl2-CsPbBr3 perovskite thin film diode-type photoelectric sensor.

[0117] Figure 10 This is a schematic diagram of the photoelectric characteristic curves of the CsPbBrCl2-CsPbBr3 perovskite thin film bidirectional diode-type photoelectric sensor in an embodiment of the present invention.

[0118] In some specific embodiments of the present invention, reference is made to Figure 10 In the absence of light, the bidirectional CsPbBrCl2-CsPbBr3 perovskite thin-film diode photodetector exhibits almost no current flow. When the light wavelength is greater than 500 nm, the photodetector remains unconducted, again showing almost no current flow. When the light wavelength is less than 500 nm but greater than 420 nm, the photodetector conducts in the forward direction, exhibiting a certain forward voltage photoresponse. When the light wavelength is less than 420 nm, the photodetector conducts in the reverse direction, exhibiting a certain reverse photoresponse.

[0119] In some specific embodiments of the present invention, in step S211, lead halide is deposited onto a portion of the upper surface of the substrate using a vapor phase evaporation method, then cesium halide is deposited onto the upper surface of the lead halide, and finally thermal annealing is performed to form a first perovskite thin film layer and a second perovskite thin film layer on a portion of the upper surface of the substrate, wherein the first perovskite thin film layer and the second perovskite thin film layer are separated on a portion of the upper surface of the substrate by a portion of the organic semiconductor layer.

[0120] Specifically, the steps include:

[0121] The HBr-APTES monolayer-treated substrate was attached to the top of the thermal evaporation equipment cavity and rotated at 10 rpm under a pressure of 10. -5 Under the condition of Pa, a beam source furnace containing the precursor PbBr2 is heated and deposited on a portion of the upper surface of the substrate at a speed of 0.1 nm / s.

[0122] Then at a pressure of 10 -5Under the condition of Pa, the beam source furnace containing the precursor CsBr is heated so that it evaporates at the same rate and sinks to the top surface of PbBr2.

[0123] The HBr-APTES monolayer-treated substrate was attached to the top of the thermal evaporation equipment cavity and rotated at 10 rpm under a pressure of 10. -5 Under the condition of Pa, a beam source furnace containing the precursor PbI2 is heated and deposited on a portion of the upper surface of the substrate at a speed of 0.1 nm / s.

[0124] Then at a pressure of 10 -5 Under the condition of Pa, the beam source furnace containing the precursor CsBr is heated so that it evaporates at the same rate and sinks to the top surface of PbI2.

[0125] Finally, the film was thermally annealed in air at 100°C for 60 min to obtain a continuous and uniform CsPbBr3-CsPbI2Br perovskite film layer.

[0126] In some specific embodiments of the present invention, in step S212, an organic semiconductor layer is formed, and a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the first perovskite thin film layer and a portion of the upper surface of the second perovskite thin film layer, and the remaining portion of the organic semiconductor layer is disposed on the upper surface of the substrate between the first perovskite thin film layer and the second perovskite thin film layer. In step S213, the positive electrode is disposed on either the upper surface of the first perovskite thin film layer or the upper surface of the second perovskite thin film layer, and the negative electrode is disposed on the other of the upper surface of the first perovskite thin film layer and the upper surface of the second perovskite thin film layer.

[0127] Specifically, the process includes the following steps: using a stainless steel mask, depositing a C8-BTBT layer and a gold electrode with a thickness of 300 nm on a portion of the upper surface of the substrate, a portion of the upper surface of the CsPbBr3 perovskite thin film layer with a thickness of 300 nm, and a portion of the upper surface of the CsPbI2Br perovskite thin film layer with a thickness of 300 nm, thereby fabricating a CsPbBr3-CsPbI2Br perovskite thin film diode-type photoelectric sensor.

[0128] Figure 11 This is a schematic diagram of the photoelectric characteristic curves of the CsPbBr3-CsPbI2Br perovskite thin film bidirectional diode-type photoelectric sensor in an embodiment of the present invention.

[0129] In some specific embodiments of the present invention, reference is made to Figure 11The bidirectional CsPbBr3-CsPbI2Br perovskite thin-film diode photodetector exhibits almost no current flow in the absence of light. When the light wavelength is greater than 620 nm, the photodetector remains unconducted, again showing almost no current flow. When the light wavelength is less than 620 nm but greater than 500 nm, the photodetector conducts in the forward direction, exhibiting a certain forward voltage-light response. When the light wavelength is less than 500 nm, the photodetector conducts in the reverse direction, exhibiting a certain reverse light response.

[0130] In some specific embodiments of the present invention, in step S201, PbI2 is deposited onto a portion of the upper surface of the flexible substrate using a vapor phase evaporation method, then CsBr is deposited onto the upper surface of PbI2, and finally a thermal annealing process is performed to form the CsPbI2Br perovskite thin film layer on the portion of the upper surface of the flexible substrate.

[0131] Specifically, the steps include:

[0132] A flexible substrate treated with an HBr-APTES monolayer was attached to the top of the cavity of the thermal evaporation equipment and rotated at 10 rpm under a pressure of 10. -5 Under the condition of Pa, a beam source furnace containing the precursor PbI2 is heated and deposited on a portion of the upper surface of the flexible substrate at a rate of 0.1 nm / s.

[0133] Then at a pressure of 10 -5 Under the condition of Pa, the beam source furnace containing the precursor CsBr is heated so that it evaporates at the same rate and sinks to the top surface of PbI2.

[0134] Finally, the film was thermally annealed in air at 120°C for 40 min to obtain a continuous and uniform CsPbI2Br perovskite film layer.

[0135] In some specific embodiments of the present invention, in step S202, an organic semiconductor layer is formed, and a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the flexible substrate, while the remaining portion of the organic semiconductor layer is disposed on a portion of the upper surface of the CsPbI2Br perovskite thin film layer; in step S203, the positive electrode is formed on the upper surface of the CsPbI2Br perovskite thin film layer, and the negative electrode is formed on the upper surface of the organic semiconductor layer.

[0136] Specifically, the process includes the following steps: using a stainless steel mask, depositing a C8-BTBT and gold electrode with a thickness of 300 nm on a portion of the upper surface of the flexible substrate and a portion of the upper surface of the CsPbI2Br perovskite thin film layer with a thickness of 300 nm, thereby fabricating a unidirectional flexible CsPbI2Br perovskite thin film diode-type photoelectric sensor.

[0137] Figure 12 This is a schematic diagram of the change in photocurrent of a unidirectional flexible CsPbI2Br perovskite thin film diode photoelectric sensor with the number of bending cycles at a bending angle of 30°, as described in an embodiment of the present invention. Figure 13 This is a schematic diagram illustrating the change of photocurrent over time in a unidirectional flexible CsPbI2Br perovskite thin-film diode photoelectric sensor after different bending angles, as shown in an embodiment of the present invention.

[0138] In some specific embodiments of the present invention, reference is made to Figure 12 and Figure 13 The unidirectional flexible CsPbI2Br perovskite thin-film diode photoelectric sensor exhibits extremely small changes in photocurrent with the number of bends at a bending angle of 30°. Furthermore, the photocurrent remains essentially constant over time after different bending angles. Therefore, the unidirectional flexible CsPbI2Br perovskite thin-film diode photoelectric sensor possesses excellent mechanical flexibility characteristics.

[0139] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the invention as set forth in the claims. Furthermore, the invention described herein may have other embodiments and can be implemented or carried out in various ways.

Claims

1. A diode-type photoelectric sensor, characterized in that, include: HBr-APTES monolayer treated substrate; A perovskite thin film layer is disposed on a portion of the upper surface of the substrate. The perovskite thin film layer is prepared by chemical vapor deposition, and the material of the perovskite thin film layer includes lead halide and cesium halide, wherein the molar ratio of lead halide to cesium halide is 1:

1. The perovskite thin film layer includes a first perovskite thin film layer and a second perovskite thin film layer, and the first perovskite thin film layer and the second perovskite thin film layer are separated by a partial organic semiconductor layer on a portion of the upper surface of the substrate. A positive electrode is disposed on either the upper surface of the first perovskite thin film layer or the upper surface of the second perovskite thin film layer, and a negative electrode is disposed on the other of the upper surface of the first perovskite thin film layer and the upper surface of the second perovskite thin film layer. An organic semiconductor layer is partially disposed on a portion of the upper surface of the substrate, and the remaining portion of the organic semiconductor layer is disposed on a portion of the upper surface of the perovskite thin film layer; as well as Electrodes, including positive and negative electrodes; The lead halide is selected from any one of lead chloride, lead bromide and lead iodide, and the cesium halide is selected from any one of cesium chloride, cesium bromide and cesium iodide.

2. The diode-type photoelectric sensor according to claim 1, characterized in that, The thickness of the perovskite thin film layer and the thickness of the organic semiconductor layer are both 50 nm to 1 μm.

3. The diode-type photoelectric sensor according to claim 1, characterized in that, The thickness of the first perovskite film layer is the same as the thickness of the second perovskite film layer, and the spacing between the first perovskite film layer and the second perovskite film layer is 100μm~200μm.

4. The diode-type photoelectric sensor according to claim 1, characterized in that, The first perovskite thin film layer and the second perovskite thin film layer are arranged symmetrically about the central axis of the substrate.

5. The diode-type photoelectric sensor according to claim 1, characterized in that, The organic semiconductor layer is made of either C8-BTBT or DNTT.

6. The diode-type photoelectric sensor according to claim 1, characterized in that, The substrate is a flexible substrate, and the material of the flexible substrate is either PI or PET.

7. The diode-type photoelectric sensor according to claim 1, characterized in that, The positive electrode and the negative electrode are made of conductive materials, including any one of gold, nickel, platinum, tungsten and silver.

8. A method for fabricating a diode-type photoelectric sensor, characterized in that, Includes the following steps: S1: A substrate that provides HBr-APTES monolayer treatment; S2: After forming a perovskite thin film layer on the upper surface of the substrate using chemical vapor deposition, an organic semiconductor layer, a positive electrode, and a negative electrode are formed, with a portion of the organic semiconductor layer disposed on a portion of the upper surface of the substrate, and the remaining portion of the organic semiconductor layer disposed on a portion of the upper surface of the perovskite thin film layer, including: S211: Lead halide is deposited onto a portion of the upper surface of the substrate using chemical vapor deposition, then cesium halide is deposited onto the upper surface of the lead halide, and finally thermal annealing is performed to form a first perovskite thin film layer and a second perovskite thin film layer on a portion of the upper surface of the substrate, wherein the first perovskite thin film layer and the second perovskite thin film layer are separated on a portion of the upper surface of the substrate by a portion of the organic semiconductor layer; S212: An organic semiconductor layer is formed, and a portion of the organic semiconductor layer is disposed on a portion of the upper surface of the first perovskite thin film layer and a portion of the upper surface of the second perovskite thin film layer, and the remaining portion of the organic semiconductor layer is disposed on the upper surface of the substrate between the first perovskite thin film layer and the second perovskite thin film layer. S213: The positive electrode is disposed on either the upper surface of the first perovskite thin film layer or the upper surface of the second perovskite thin film layer, and the negative electrode is disposed on the other of the upper surface of the first perovskite thin film layer and the upper surface of the second perovskite thin film layer. Furthermore, the material of the perovskite thin film layer includes lead halide and cesium halide, the molar ratio of lead halide and cesium halide is 1:1, the lead halide is selected from any one of lead chloride, lead bromide and lead iodide, and the cesium halide is selected from any one of cesium chloride, cesium bromide and cesium iodide.

9. The preparation method according to claim 8, characterized in that, The temperature of the heat annealing treatment is 100℃~150℃, and the time of the heat annealing treatment is 30min~60min.

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