Broadband tunable photodetector based on perovskite micron-wire waveguide and its preparation method

Abstract

A broadband tunable photodetector based on perovskite micron-wire waveguides and a preparation method thereof relate to the field of photoelectric detection technology, solving the problem of complexity of existing systems capable of achieving tunable detection in multiple bands. The invention comprises a substrate, a dielectric layer, a plurality of waveguide units disposed on the dielectric layer, and metal electrodes, wherein the perovskite materials used in any two waveguide units are different; the waveguide units comprise a first optical waveguide disposed on the dielectric layer and a second optical waveguide disposed on the dielectric layer, the first optical waveguide and the second optical waveguide being perpendicular to each other, the second optical waveguide connecting the first optical waveguide, the first optical waveguide being located between the two ends of the second optical waveguide, and the second optical waveguide being located between the two ends of the first optical waveguide; the number of the first optical waveguides being at least two and both ends being connected to the metal electrodes, or the number of the second optical waveguides being at least two and both ends being connected to the metal electrodes. The invention balances broadband response and spectral resolution, reducing the complexity of the system.

Description

Technical Field

[0001] The present invention relates to the field of photoelectric detection technology, and in particular to a broadband tunable photodetector based on perovskite micron wire waveguide and a preparation method thereof. Background Art

[0002] Broadband tunable photodetection has important applications in fields such as information communication, environmental observation, medical imaging, and military reconnaissance. As information devices develop toward miniaturization and integration, photodetectors based on two-dimensional materials can directly utilize the intrinsic band tunability of two-dimensional materials to detect light over a wide wavelength range, showing promising application prospects in the field of broadband tunable photodetection. The method for achieving broadband tunable photodetection is to modulate the absorption or electrical properties of the two-dimensional material itself through gate voltage, thereby adjusting the photoelectric response and achieving broadband tunable detection. However, this design often struggles to balance broadband response and spectral resolution. In other words, it is difficult to achieve selective detection and identification of specific wavelengths while simultaneously detecting across a wide spectrum. Furthermore, using this structure to achieve tunable detection across multiple wavelengths requires the use of multiple bias gate voltages, which increases system complexity to a certain extent. Summary of the Invention

[0003] In order to solve the above problems, the present invention provides a broadband tunable photodetector based on perovskite micron-wire waveguide and a preparation method thereof.

[0004] The technical solutions adopted by the present invention to solve the technical problems are as follows:

[0005] A broadband tunable photodetector based on perovskite micron wire waveguide includes a substrate, a dielectric layer arranged on the substrate, a plurality of waveguide units arranged on the dielectric layer, and a metal electrode, wherein the perovskite materials used by any two of the waveguide units are different; the waveguide unit includes a first optical waveguide line arranged on the dielectric layer and a second optical waveguide line arranged on the dielectric layer, the first optical waveguide line and the second optical waveguide line are perpendicular to each other, the second optical waveguide line is connected to the first optical waveguide line, the first optical waveguide line is located between the two ends of the second optical waveguide line, and the second optical waveguide line is located between the two ends of the first optical waveguide line; the number of the first optical waveguide lines is at least two and both ends of the first optical waveguide line are connected to the metal electrodes, or the number of the second optical waveguide lines is at least two and both ends of the second optical waveguide line are connected to the metal electrodes.

[0006] The method for preparing a broadband tunable photodetector based on a perovskite micron-wire waveguide comprises the following steps: preparing a substrate covered with a dielectric layer, preparing multiple film-forming substrates; preparing a single-crystalline perovskite film on each film-forming substrate, and transferring the single-crystalline perovskite film onto the dielectric layer; using focused ion beam technology to prepare the single-crystalline perovskite film on the dielectric layer to obtain multiple waveguide units, wherein the number of the waveguide units is equal to the number of the film-forming substrates; and preparing a metal electrode by evaporation on the dielectric layer to obtain a broadband tunable photodetector based on the perovskite micron-wire waveguide.

[0007] The method for preparing the broadband tunable photodetector based on perovskite micron-wire waveguide comprises the following steps:

[0008] Step 1: prepare a substrate covered with a dielectric layer, cover the dielectric layer with a layer of photoresist, and etch a waveguide groove structure;

[0009] Step 2: Combine the mask and take a perovskite DMF solution. Use a knife coating method on a glass slide to prepare a waveguide unit in the waveguide groove structure not covered by the mask. After the DMF evaporates, a waveguide unit is prepared.

[0010] Step 3: Repeat step 2 until all waveguide units are prepared; the perovskite material of the perovskite DMF solution used in any two executions of step 2 is different;

[0011] Step 4: Remove the mask and prepare metal electrodes connecting the waveguide units by evaporation to obtain a broadband tunable photodetector based on perovskite micron-wire waveguide.

[0012] The method for preparing the broadband tunable photodetector based on perovskite micron-wire waveguide comprises the following steps:

[0013] Prepare a substrate covered with a dielectric layer and multiple ITO film-forming substrate layers; coat a PTAA connecting layer on each ITO film-forming substrate layer, prepare a perovskite polycrystalline thin film on the PTAA connecting layer by a solution method, wash off the PTAA connecting layer with chlorobenzene to obtain a perovskite polycrystalline thin film, and transfer the perovskite polycrystalline thin film to the dielectric layer, wherein the perovskite materials used in any two of the perovskite polycrystalline thin films are different; use a nanoimprint template to imprint on the perovskite polycrystalline thin film, remove the nanoimprint template to obtain all waveguide units; prepare metal electrodes connecting the waveguide units by evaporation, and the broadband tunable light detector based on the perovskite micron wire waveguide is completed.

[0014] The beneficial effects of the present invention are:

[0015] The broadband tunable photodetector based on perovskite micron-wire waveguides balances broadband response with spectral resolution, enabling selective detection and identification of specific wavelengths while simultaneously detecting across a wide spectrum. This technology leverages the strong room-temperature photoluminescence, high carrier mobility, and low propagation loss of perovskites to achieve highly sensitive light transmission and reception. By utilizing the perovskite micron-wire waveguide structure, perovskite micron-wires with different wavelength-selective structures are integrated onto a single substrate, achieving broadband tunable detection on the same substrate. This broadband tunable photodetector avoids the traditional use of multiple bias gate voltages, thereby reducing system complexity.

[0016] The preparation method of the broadband tunable photodetector based on the perovskite micron wire waveguide of the present invention is simple to operate and can obtain a high-quality broadband tunable photodetector. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic structural diagram of the broadband tunable photodetector based on perovskite micron-wire waveguide of the present invention.

[0018] Figure 2 This is a structural diagram of the silicon substrate and the dielectric layer in Example 1 of the method for preparing a broadband tunable photodetector based on perovskite micron-wire waveguide of the present invention.

[0019] Figure 3 This is a structural diagram of the first film-forming substrate in Example 1 of the method for preparing a broadband tunable photodetector based on perovskite micron-wire waveguide of the present invention.

[0020] Figure 4 This is a structural diagram of the second film-forming substrate in Example 1 of the method for preparing a broadband tunable photodetector based on perovskite micron-wire waveguide of the present invention.

[0021] Figure 5 This is a structural diagram of the third film-forming substrate in Example 1 of the method for preparing a broadband tunable photodetector based on perovskite micron-wire waveguide of the present invention.

[0022] Figure 6 This is a structural diagram of a single crystal perovskite film obtained in Example 1 of the method for preparing a broadband tunable photodetector based on perovskite micron-wire waveguide of the present invention.

[0023] Figure 7 This is a structural diagram of the method for preparing a broadband tunable photodetector based on a perovskite micron-wire waveguide in Example 1 of the present invention before performing focused ion beam operation.

[0024] Figure 8 This is a schematic diagram of the waveguide groove structure in Example 2 of the method for preparing a broadband tunable photodetector based on perovskite micron-wire waveguide of the present invention.

[0025] Figure 9 This is a diagram of the preparation process of the first waveguide unit in Example 2 of the preparation method of the perovskite micron-wire waveguide-based broadband tunable optical detector of the present invention.

[0026] Figure 10 This is a diagram of the preparation process of the second waveguide unit in Example 2 of the preparation method of the perovskite micron-wire waveguide-based broadband tunable optical detector of the present invention.

[0027] Figure 11 This is a diagram of the preparation process of the third waveguide unit in Example 2 of the preparation method of the perovskite micron-wire waveguide-based broadband tunable optical detector of the present invention.

[0028] Figure 12 This is a structural diagram of the broadband tunable photodetector obtained in Example 2 of the method for preparing a broadband tunable photodetector based on perovskite micron-wire waveguide of the present invention.

[0029] Figure 13 This is a schematic diagram of the nanoimprint template imprinting in Example 3 of the method for preparing a broadband tunable photodetector based on perovskite micron-wire waveguide of the present invention.

[0030] In the figure: 1. substrate, 2. dielectric layer, 3. first waveguide unit, 4. second waveguide unit, 5. third waveguide unit, 6. first optical waveguide line, 7. second optical waveguide line, 8. metal electrode, 9. first film-forming substrate, 10. first single crystal perovskite thin film, 11. second film-forming substrate, 12. second single crystal perovskite thin film, 13. third film-forming substrate, 14. third single crystal perovskite thin film, 15. SU-8 photoresist, 16. waveguide groove structure, 17. nanoimprint template. DETAILED DESCRIPTION

[0031] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0033] Broadband tunable photodetectors based on perovskite microwire waveguides, such as Figure 1, including a substrate 1, a dielectric layer 2, a waveguide unit and a metal electrode 8. There are multiple waveguide units. The substrate 1, the dielectric layer 2 and the waveguide unit are arranged sequentially from bottom to top, the dielectric layer 2 is arranged on the substrate 1, the waveguide unit is arranged on the dielectric layer 2, the metal electrode 8 is arranged on the dielectric layer 2, and the metal electrode 8 connects the waveguide units. All waveguide units are made of perovskite. The perovskite materials used by any two waveguide units are different to achieve different light response wavelengths of different waveguide units and different transmission bands of different waveguide units. Each waveguide unit corresponds to a perovskite material. The perovskite material components used by any two waveguide units are different, that is, the components are not completely the same (the constituent elements of the perovskite materials between any two waveguide units are not completely the same), or the perovskite material components used by any two waveguide units are the same but the content of the components is not completely the same. The waveguide unit includes a first optical waveguide 6 and a second optical waveguide 7 disposed on a dielectric layer 2. The first optical waveguide 6 and the second optical waveguide 7 are perpendicular to each other. The first optical waveguide 6 connects to the second optical waveguide 7. The first optical waveguide 6 is located between the ends of the second optical waveguide 7, and the second optical waveguide 7 is located between the ends of the first optical waveguide 6. The middle of the first optical waveguide 6 is connected to the middle of the second optical waveguide 7, where the middle refers to a non-end portion. There are at least two first optical waveguides 6, or at least two second optical waveguides 7, or both. Metal electrodes 8 connect the ends of the second optical waveguide 7. There are at least two first optical waveguides 6 and both ends of the first optical waveguide 6 are connected to the metal electrodes 8, or there are at least two second optical waveguides 7 and both ends of the second optical waveguide 7 are connected to the metal electrodes 8. The number of first optical waveguides 6 is at least two and / or the number of second optical waveguides 7 is at least two, and the metal electrode 8 includes a metal positive electrode and a metal negative electrode. If the number of first optical waveguides 6 is at least two but the number of second optical waveguides 7 is one, the metal electrode 8 is connected to the first optical waveguides 6, specifically, the metal positive electrode is connected to one end of each first optical waveguide 6, and the metal negative electrode is connected to the other end of each first optical waveguide 6. If the number of second optical waveguides 7 is at least two but the number of first optical waveguide 6 is one, the metal electrode 8 is connected to the second optical waveguide 7, specifically, the metal positive electrode is connected to one end of each second optical waveguide 7, and the metal negative electrode is connected to the other end of each second optical waveguide 7. If the number of second optical waveguides 7 and the number of first optical waveguides 6 are both at least two but one, the metal electrode 8 is connected to the first optical waveguide 6 or the second optical waveguide 7.

[0034] For example, there are three waveguide units, which are respectively referred to as the first waveguide unit 3, the second waveguide unit 4 and the third waveguide unit 5 for distinction. The materials of the first waveguide unit 3, the second waveguide unit 4 and the third waveguide unit 5 can be MAPbI3, MAPbBrx I 3-x , MAPbBr3, 3>x>0 (the components are not completely the same); or, the materials of the first waveguide unit 3, the second waveguide unit 4 and the third waveguide unit 5 can be MAPbBr x I 3-x MAPbBr y I 3-y MAPbBr z I 3-z , 3>y>0, 3>z>0, x≠y≠z (in this case, the components are the same but the content of the components is not exactly the same); alternatively, the materials of the first waveguide unit 3, the second waveguide unit 4 and the third waveguide unit 5 can be MAPbBr x I 3-x MAPbBr y I 3-y MAPb 1-c Sn c I 3-a Br a , where 0<c<0.1, 0<a<3, which are not exhaustively listed here. Figure 1 Each waveguide unit includes a first optical waveguide wire 6 and three second optical waveguide wires 7. The three second optical waveguide wires 7 are sequentially arranged in the middle of the first optical waveguide wire 6, that is, the second optical waveguide wire 7 is not arranged at the end of the first optical waveguide wire 6. The first optical waveguide wire 6 is connected to the middle of the second optical waveguide wire 7. One end of the first optical waveguide wire 6 is called end A and the other end is called end B. One ends of the three second optical waveguide wires 7 are respectively end C1, end C2 and end C3. The other ends of the second optical waveguide wires 7 corresponding to end C1, end C2 and end C3 are respectively end D1, end D2 and end D3. Incident light is incident on end A of the first optical waveguide wire 6, and electrical signals can be received at ends C1, end C2, end C3, end D1, end D2 and end D3 of the second optical waveguide wire 7, thereby achieving high-sensitivity detection.

[0035] The first optical waveguide 6 and the second optical waveguide 7 are both micrometer-wire structures, i.e., their cross-sectional diameters range from several hundred nanometers to several micrometers, and their lengths range from several to several tens of micrometers. The substrate 1 is made of silicon. The dielectric layer 2 is made of silicon dioxide or hafnium oxide.

[0036] The present invention's broadband tunable photodetector based on perovskite micron-wire waveguides utilizes a cross-shaped perovskite micron-wire waveguide for efficient light propagation and combines homogeneous perovskite with the micron-wire waveguide for highly sensitive reception and detection. By integrating perovskite micron-wire structures with varying photoresponses onto a single substrate (1), the device enables wide-band light detection.

[0037] The present invention's broadband tunable photodetector based on perovskite micron-wire waveguides balances broadband response with spectral resolution, enabling selective detection and identification of specific wavelengths while simultaneously detecting across a wide spectrum. This technology leverages the perovskite's strong room-temperature photoluminescence, high carrier mobility, and low propagation loss to achieve highly sensitive light transmission and reception. By utilizing the perovskite micron-wire waveguide structure, perovskite micron-wires with different wavelength-selective structures are integrated onto a single substrate (1), achieving broadband tunable detection on the same substrate. This broadband tunable photodetector avoids the traditional use of multiple bias gate voltages, thereby reducing system complexity.

[0038] The present invention provides three implementation methods for preparing a broadband tunable photodetector based on perovskite micron-wire waveguide. By adopting the following method, a high-quality broadband tunable photodetector can be obtained.

[0039] Embodiment 1: Prepare a target substrate, i.e., a silicon substrate 1 covered with a silicon dioxide layer (a 300 nm thick silicon dioxide layer is covered on the silicon substrate 1). Figure 2 and three A film-forming substrate (perovskite single crystal substrate embedded in PDMS support) such as Figures 3 to 5 ; Using a solution-based epitaxial growth and transfer method assisted by photolithography (using a PI mask), a high-quality first single crystal perovskite film 10 is prepared on a first film-forming substrate 9 as Figure 6 , and transfer the first single crystal perovskite film 10 to the silicon dioxide layer, and use the solution epitaxial growth and transfer method assisted by photolithography to prepare a high-quality second single crystal perovskite film 12 on the second film-forming substrate 11. Figure 6 , and transfer the second single crystal perovskite film 12 to the silicon dioxide layer, and use the solution epitaxial growth and transfer method assisted by photolithography to prepare a high-quality third single crystal perovskite film 14 on the third film-forming substrate 13. Figure 6 , and transfer the third single crystal perovskite film 14 to the silicon dioxide layer. The components and / or component contents of the three single crystal perovskite films are different. At this time, the following is obtained: Figure 7 In the structure shown, a single crystal waveguide is prepared by focused ion beam, that is, three waveguide units are obtained; a metal electrode 8 is prepared by evaporation to obtain a broadband tunable photodetector based on perovskite micron wire waveguide.

[0040] Embodiment 2: prepare a target substrate, cover the target substrate with a layer of SU-8 photoresist 15, and etch a waveguide groove structure 16 on the SU-8 photoresist 15, as shown in FIG. Figure 8 , the waveguide groove structure 16 corresponds to the multiple waveguide units to be obtained; combined with the mask, take a perovskite DMF solution, such as Figure 9, a first waveguide unit 3 is prepared in the waveguide groove structure 16 not covered by the mask by a knife coating method on a glass slide, and after DMF (N,N-dimethylformamide) evaporates, the first waveguide unit 3 is prepared; combined with the mask, a perovskite DMF solution different from the previous perovskite DMF solution is taken, such as Figure 10 , a second waveguide unit 4 is prepared in the waveguide groove structure 16 not covered by the mask by knife coating through a glass slide, and after DMF (N,N-dimethylformamide) evaporates, the second waveguide unit 4 is prepared; combined with the mask, a perovskite DMF solution different from the first two perovskite DMF solutions is taken, such as Figure 11 , a third waveguide unit 5 is prepared in the waveguide groove structure 16 not covered by the mask by knife coating on a glass slide, and after DMF (N,N-dimethylformamide) evaporates, the third waveguide unit 5 is prepared; the mask is removed to obtain a perovskite waveguide structure, that is, three waveguide units are obtained, and the above-mentioned photoresist can be etched away or retained; a metal electrode 8 is prepared by evaporation to obtain a broadband tunable photodetector based on a perovskite micron wire waveguide, such as Figure 12 .

[0041] Implementation method three: prepare a target substrate and three ITO film-forming substrate layers; on the first ITO film-forming substrate layer, coat a first PTAA connecting layer (PTAA is poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine]), prepare a first perovskite polycrystalline thin film on the first PTAA connecting layer by a solution method, wash off the first PTAA connecting layer with chlorobenzene to obtain a first perovskite polycrystalline thin film, and transfer the first perovskite polycrystalline thin film to the target substrate; on the second ITO film-forming substrate layer, coat a second PTAA connecting layer, and on the second ITO film-forming substrate layer by a solution method. A second perovskite polycrystalline film is prepared on the PTAA connecting layer, the second PTAA connecting layer is washed off with chlorobenzene to obtain a second perovskite polycrystalline film, and the second perovskite polycrystalline film is transferred to the target substrate; a third PTAA connecting layer is coated on the third ITO film-forming substrate layer, a third perovskite polycrystalline film is prepared on the third PTAA connecting layer by a solution method, the third PTAA connecting layer is washed off with chlorobenzene to obtain a third perovskite polycrystalline film, and the third perovskite polycrystalline film is transferred to the target substrate; a nanoimprint template 17 is prepared according to all the waveguide units to be obtained, as shown in FIG. Figure 13 The nanoimprint template 17 is imprinted on three perovskite polycrystalline films. After removing the template, a perovskite polycrystalline waveguide is obtained, that is, three waveguide units are obtained. The metal electrode 8 is prepared by evaporation to obtain a broadband tunable light detector based on the perovskite micron wire waveguide.

Claims

1. A broadband tunable photodetector based on perovskite micron-wire waveguide, characterized in that: The invention comprises a substrate (1), a dielectric layer (2) arranged on the substrate (1), a plurality of waveguide units arranged on the dielectric layer (2), and a metal electrode (8), wherein the perovskite materials used by any two of the waveguide units are different; the waveguide unit comprises a first optical waveguide wire (6) arranged on the dielectric layer (2) and a second optical waveguide wire (7) arranged on the dielectric layer (2), the first optical waveguide wire (6) and the second optical waveguide wire (7) are perpendicular to each other, the second optical waveguide wire (7) is connected to the first optical waveguide wire (6), the first optical waveguide wire (6) is located between the two ends of the second optical waveguide wire (7), and the second optical waveguide wire (7) is located between the two ends of the first optical waveguide wire (6); the number of the first optical waveguide wire (6) is at least two and both ends of the first optical waveguide wire (6) are connected to the metal electrode (8), or the number of the second optical waveguide wire (7) is at least two and both ends of the second optical waveguide wire (7) are connected to the metal electrode (8).

2. The broadband tunable photodetector based on perovskite micron-wire waveguide according to claim 1, characterized in that: The different waveguide units transmit different wavebands.

3. The broadband tunable photodetector based on perovskite microwire waveguide according to claim 1, characterized in that: The metal electrode (8) is arranged on the dielectric layer (2).

4. The broadband tunable photodetector based on perovskite microwire waveguide according to claim 1, characterized in that: The perovskite material components used by any two waveguide units are not completely the same, or the perovskite material components used by any two waveguide units are the same but the content of the components is not completely the same.

5. The method for preparing a broadband tunable photodetector based on a perovskite micron-wire waveguide according to any one of claims 1 to 4, wherein: The method comprises the following steps: preparing a substrate (1) covered with a dielectric layer (2), and preparing a plurality of film-forming substrates; preparing a single-crystal perovskite film on each film-forming substrate, and transferring the single-crystal perovskite film onto the dielectric layer (2); using a focused ion beam technique to prepare the single-crystal perovskite film on the dielectric layer (2) to obtain a plurality of waveguide units, wherein the number of the waveguide units is equal to the number of the film-forming substrates; and preparing a metal electrode (8) by vapor deposition on the dielectric layer (2) to obtain a broadband tunable light detector based on the perovskite micrometer wire waveguide.

6. The method for preparing a broadband tunable photodetector based on a perovskite micron-wire waveguide according to any one of claims 1 to 4, wherein: The steps include: Step 1: preparing a substrate (1) covered with a dielectric layer (2), covering the dielectric layer (2) with a layer of photoresist, and etching a waveguide groove structure (16); Step 2: Combined with the mask, take a perovskite DMF solution and use a knife coating method to prepare a waveguide unit in the waveguide groove structure (16) not covered by the mask through a glass slide. After the DMF evaporates, a waveguide unit is prepared; Step 3: Repeat step 2 until all waveguide units are prepared; the perovskite material of the perovskite DMF solution used in any two executions of step 2 is different; Step 4: remove the mask, and prepare metal electrodes (8) connected to the waveguide units by evaporation to obtain a broadband tunable photodetector based on perovskite micron wire waveguide.

7. The method for preparing a broadband tunable photodetector based on a perovskite micron-wire waveguide according to any one of claims 1 to 4, characterized in that: The steps include: A substrate (1) covered with a dielectric layer (2) and multiple ITO film-forming substrate layers are prepared; a PTAA connecting layer is coated on each ITO film-forming substrate layer, a perovskite polycrystalline film is prepared on the PTAA connecting layer by a solution method, the PTAA connecting layer is washed off with chlorobenzene to obtain a perovskite polycrystalline film, and the perovskite polycrystalline film is transferred to the dielectric layer (2), wherein the perovskite materials used in any two of the perovskite polycrystalline films are different; a nanoimprint template (17) is used to imprint on the perovskite polycrystalline film, and the nanoimprint template (17) is removed to obtain all waveguide units; a metal electrode (8) connecting the waveguide units is prepared by evaporation, and a broadband tunable optical detector based on the perovskite micrometer wire waveguide is prepared.

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